{VERSION 5 0 "IBM INTEL NT" "5.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 1 }{CSTYLE "2D Comment" 2 18 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 } {CSTYLE "" 0 21 "" 0 1 0 0 0 1 0 0 0 0 2 0 0 0 0 1 }{CSTYLE "" -1 256 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 257 "" 1 14 0 0 0 0 0 0 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 258 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 259 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 260 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 261 "" 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 1 }{CSTYLE "" -1 262 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 263 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 } {CSTYLE "" -1 264 "" 1 14 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 265 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 266 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 267 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 268 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 } {CSTYLE "" -1 269 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 270 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 271 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 272 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 273 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 } {CSTYLE "" -1 274 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 275 "" 1 18 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 276 "" 1 14 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 277 "" 1 10 0 0 0 0 0 0 0 0 0 0 0 0 0 1 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Headi ng 2" -1 4 1 {CSTYLE "" -1 -1 "Times" 1 14 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 2 1 0 1 0 2 2 0 1 }{PSTYLE "Heading 3" -1 5 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 1 1 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Normal" -1 256 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 1 0 0 0 0 1 0 1 0 2 2 0 1 }} {SECT 0 {EXCHG {PARA 256 "" 0 "" {TEXT -1 0 "" }{TEXT 274 0 "" }{TEXT 275 23 "Calculus IV with Maple\n" }{TEXT 276 32 "Copyright 2002, Dr. J ack Wagner\n" }{TEXT -1 30 "j.wagner@intelligentsearch.com" }}}{EXCHG {PARA 4 "" 0 "" {TEXT -1 61 "\nLesson 4: Constrained Optimization with Lagrange Multipliers" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 5 "" 0 "" {TEXT -1 128 "Topics: The method of Lagrange multiplie rs for solving optimization problems that have constraints is illustra ted geometrically." }}{PARA 5 "" 0 "" {TEXT 277 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 198 "The problem of optimization, just as in the si ngle variable case, involves maximizing or minimizing some function su bject to a set of constraints. For ease of visualization we are going to work in " }{XPPEDIT 18 0 "R^3;" "6#*$%\"RG\"\"$" }{MPLTEXT 0 21 1 " " }{TEXT -1 270 "with two constraint equations, but the ideas and me thods are identical for higher dimensions and larger constraint sets. \+ Formal proofs of the method of Lagrange multipliers abound. What we \+ present here is a geometric picture and geometric explanation of the p rocedure." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 258 11 "Example 4.1" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 45 "We suppose that we are required to optimi ze " }{XPPEDIT 18 0 "F(x,y,z) = y+2*z-x^2;" "6#/-%\"FG6%%\"xG%\"yG%\" zG,(F(\"\"\"*&\"\"#F+F)F+F+*$F'F-!\"\"" }{TEXT -1 61 " subject to two constraints: F is restricted to the sphere, " }{XPPEDIT 18 0 "x^2+y^2 +z^2 = 25;" "6#/,(*$%\"xG\"\"#\"\"\"*$%\"yGF'F(*$%\"zGF'F(\"#D" } {TEXT -1 29 " and also to the cylinder, " }{XPPEDIT 18 0 "x^2+y^2 = \+ 9;" "6#/,&*$%\"xG\"\"#\"\"\"*$%\"yGF'F(\"\"*" }{TEXT -1 0 "" } {MPLTEXT 0 21 6 ".\n \n" }{TEXT -1 86 "First, examine a plot of the \+ two constraints together with several level sets of F. \n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 79 "restart:with(VectorCalculus):with(L inearAlgebra):with(plots): with(plottools): " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "F := y + 2 * z-x^2;" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 177 "Now we create plot struc tures for several level sets of F. The multiple 5 in the expression 5 * k is necessary to separate the sets by a sufficient amount to assur e visibility." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 153 "P1 := k - > implicitplot3d(F = 9 * k, x = -10..10, y = -10..10, z = -10..10, axe s = boxed, style=patchnogrid, numpoints=2000):\nS1 := seq(P1(k), k = 1 ..2):" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 74 "Now we define the constraints and create plot structures \+ for their graphs." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 126 "P2 := sphere([0,0,0], 5, color=blue):\nP3 := cylinder([0,0,-8], 3, 16, capp ed=false, style=wireframe, color=red, thickness=3):\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 118 "By inspection of the constraint equation s they intersect where z = \2614. This intersection is plotted as a \+ spacecurve." }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 166 "S2 := spacecurve(\{[x, sqrt(9-x^2), 4], [x, -sqrt(9- x^2), 4], [x, sqrt(9-x^2), -4], [x, -sqrt(9-x^2), -4]\}, x = -3..3, nu mpoints = 1000, color = black, thickness = 2):" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 68 "display(S1, P2, P3, S2, orientation=[-75,65], \+ scaling=constrained);\011" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 204 "The cylinder and sphere intersect in two circles, S2. At an optimal poin t for F, one of the level sets must be tangent to one of the circles i n S2. Looking ahead we reproduce the plot of the level set, " } {XPPEDIT 18 0 "F^(-1);" "6#)%\"FG,$\"\"\"!\"\"" }{TEXT -1 4 "(11)" } {MPLTEXT 0 21 3 " , " }{TEXT -1 82 "the maximum of F restricted to the surfaces, together with the tangents to S2 and " }{MPLTEXT 0 21 1 " \+ " }{TEXT -1 0 "" }{XPPEDIT 18 0 "F^(-1);" "6#)%\"FG,$\"\"\"!\"\"" } {TEXT -1 4 "(11)" }{MPLTEXT 0 21 2 ", " }{TEXT -1 112 "and the gradien ts of F , the cylinder and the sphere as well as the normal plane to S 2 at the point of tangency." }{MPLTEXT 0 21 1 "\n" }}}{EXCHG {PARA 0 " " 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 25 "Function to be opt imized." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "F := y + 2 * z-x ^2:" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 12 "Constraint 1" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "C1 : = x^2 + y^2 + z^2 = 25: \011\011" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 12 "Constraint 2" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "C2 := x^2 + y^2 = 9:" }}}{EXCHG {PARA 0 " " 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 33 "Plot of intersecti on of C1 and C2" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 141 "Sa := s pacecurve(\{[x, sqrt(9-x^2), 4], [x, -sqrt(9-x^2), 4]\}, x = -3..3, \n numpoints = 1000, color = black, thickness = 2): " } }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 41 " Plot of level set of inverse image of 11." }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 94 "Sc := implicitplot3d(F = 11, x = -3..3, y = -3..5, \+ z = 0..6, color = blue, style = wireframe):" }}}{EXCHG {PARA 0 "" 0 " " {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 42 "Positive part of inters ection of C1 and C2" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 33 "e := ; \011 " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "de[x] := diff(e, x);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 33 "de[x = 0] := subs(x = 0, de[x]);\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 12 "Tangent to e" } }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 28 "T := <0, 3, 4> + s * de[x] ; " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 67 "Sb := spacecurve(eval m(T), s = -4..4, color = red, thickness = 3):\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 41 "Plot of level set of inverse image of 11." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 94 "Sc := implicitplot3d(F = 11, x = -3..3, y = -3..5, z = 0..6, color = blu e, style = wireframe):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "r := [x, y, z]:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "gF := Gra dient(F, r);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "gF := subs( x = 0, gF);\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 37 "Gradient vector of F at P = [0, 3, 4]" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 39 "G1 := <0, 3, 4> + s * evalVF(gF, );\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 74 "Sd := spacecurve(e valm(G1), s = -1.5..1.5, color = black, thickness = 3):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "gC1 := Gradient(lhs(C1), r);\n" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 40 "gC1 := subs(\{x = 0, y = 3, \+ z = 4\}, gC1);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "gC2 := Gr adient(lhs(C2), r);\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 41 "gC 2 := subs(\{x = 0, y = 3, z = 4\}, gC2);\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 27 "Gradient vector of C1 at \+ P." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "G2 := <0, 3, 4> + s * evalVF(gC1, ); \n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 27 " Gradient vector of C2 at P." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 56 "G3 := <0, 3, 4> + s * evalVF(gC2, ); \011\011 \n" } }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 26 " Plane spanned by G3 and G2" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 58 "G4 := <0, 3, 4> + evalVF(s * gC1 + t * gC2, );\011 \n" }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 84 "Se := spacecurve(\{evalm(G2 ), evalm(G3)\}, s = -0.3..0.4, color = red, thickness = 3):" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 86 "Sf := plot3d(evalm(G4), s = \+ -.3..0.4, t = -.3..0.4, color = green, style = wireframe):" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 22 "Plane ort hogonal to G1" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 56 "G5 := (-<0, 3, 4>).evalVF(gF, ) = 0; \n" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 78 "Sg := plot3d((11-y)/2, x = -2..2, y = -1..6, c olor = pink, style = wireframe):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 75 "display(Sa, Sb, Sc, Sd, Se, Sf, Sg, axes = framed, or ientation=[-130,50]);\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 105 "Refer ring to this illustration, we will identify each function, its graph a nd its plot by the same name. " }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 55 "By the implicit function theorem, the level set s of F, " }{TEXT 265 1 "\{" }{TEXT -1 1 " " }{XPPEDIT 18 0 "F^(-1);" " 6#)%\"FG,$\"\"\"!\"\"" }{TEXT -1 3 "(k)" }{TEXT 266 1 "\}" }{TEXT -1 789 ", yield surfaces. To satisfy the constraints, these are required \+ to intersect the graphs of C1 and C2. It is clear that to satisfy both constraints simultaneously, the graphs of the level sets must inters ect their intersection, one of the two circles, S2. In addition, it i s evident that the extreme values of F will occur at those points whe re a level set of F is tangent to the graph of S2. This is analogous \+ to the situation in linear programming where the optimized linear func tion must be tangent to the feasible set. Call such a point of tangen cy P. At every point the tangent line to S2 must lie in the tangent pl ane to the graphs of both C1 and C2, and, therefore, in the intersecti on of those tangent planes. In particular, this is true at P. Since, \+ at P there is a graph of" }{MPLTEXT 0 21 1 " " }{TEXT -1 0 "" }{TEXT 268 1 "\{" }{TEXT -1 1 " " }{XPPEDIT 18 0 "F^(-1);" "6#)%\"FG,$\"\"\"! \"\"" }{TEXT -1 3 "(k)" }{TEXT 269 1 "\}" }{TEXT -1 40 " tangent to S2 , for some value of k, say" }{TEXT 267 1 " " }{XPPEDIT 18 0 "k[0];" "6 #&%\"kG6#\"\"!" }{TEXT -1 2 ", " }{MPLTEXT 0 21 1 " " }{TEXT -1 80 "at this point the tangent line to S2 lies in the tangent plane to the gr aph of " }{TEXT 270 1 "\{" }{XPPEDIT 18 0 "F^(-1);" "6#)%\"FG,$\"\"\" !\"\"" }{TEXT -1 1 "(" }{XPPEDIT 18 0 "k[0];" "6#&%\"kG6#\"\"!" } {TEXT -1 1 ")" }{TEXT 271 1 "\}" }{TEXT -1 1 " " }{MPLTEXT 0 21 2 ". \+ " }{TEXT -1 602 "At each point on C1 and C2, its gradient is orthogona l to its tangent plane. Because the tangent line to S2 lies in the in tersection of the tangent planes of C1 and C2, both gradients must be \+ orthogonal to the tangent line to S2. That is, at P on S2, the gradie nt vectors to C1 and C2 lie in a plane orthogonal to the tangent to S2 , i.e. the normal plane to S2 at P. Since the gradient vectors are in dependent any vector in that plane is a linear combination of the two \+ gradients. But the gradient of F, at P, is orthogonal to its tangent \+ plane at that point, i.e. the plane tangent to the graph of" } {MPLTEXT 0 21 1 " " }{TEXT -1 0 "" }{TEXT 272 1 "\{" }{XPPEDIT 18 0 "F ^(-1);" "6#)%\"FG,$\"\"\"!\"\"" }{TEXT -1 1 "(" }{XPPEDIT 18 0 "k[0]; " "6#&%\"kG6#\"\"!" }{TEXT -1 1 ")" }{TEXT 273 1 "\}" }{TEXT -1 1 " " }{MPLTEXT 0 21 2 ". " }{TEXT -1 327 "At P where F is just tangent to S 2, the tangent plane of F must contain the tangent line to S2. The gr adient of F, therefore, is orthogonal to that tangent line and so lie s in the normal plane at P. The result of this is that the gradient of F is a linear combination of the gradients of the two constraint surf ace equations." }{MPLTEXT 0 21 2 " " }{TEXT -1 1 " " }{XPPEDIT 18 0 " grad(F) = lambda[1]*grad(C[1])+lambda[2]*grad(C[2]);" "6#/-%%gradG6#% \"FG,&*&&%'lambdaG6#\"\"\"F--F%6#&%\"CG6#F-F-F-*&&F+6#\"\"#F--F%6#&F16 #F6F-F-" }{TEXT -1 243 " This yields three equations in five unknown s. The lambdas are the Lagrange multipliers. Together with the two c onstraint equations, we have five equations in five unknowns. Impleme nting this in Maple is a lot simpler than explaining it.\n" }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "r := [x, y, z] :" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "gF := Gradient(F, r); " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 80 "gC := lambda[1] * Gradi ent(lhs(C1), r) + lambda[2] * Gradient(lhs(C2), r); \011\011 \n" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 47 "for k to 3 do eq||k := gF[k] = gC[k] od; " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 48 "Note the u se of the concatenation operator \"||\"." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }{MPLTEXT 1 0 72 "sol := solve(\{eq1, eq2, eq3, C1, C2\} , \{x, y, z, lambda[1], lambda[2]\});\011" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 62 "Now we substitute each of these sets of values in turn in to F." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 43 "V := evalf(seq(sub s(sol[k], F), k = 1..6));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 74 "From whence it is clear that F is maximized at [0, 3, 4] and minimized at \+ " }{XPPEDIT 18 0 "[`+/-`*sqrt(35)/2, -1/2, -4];" "6#7%*(%$+/-G\"\"\"-% %sqrtG6#\"#NF&\"\"#!\"\",$*&F&F&F+F,F,,$\"\"%F," }{TEXT -1 0 "" }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 100 "In order to understand this very \+ important method more thoroughly we will dissect a second example. " } }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 257 11 "Example 4.2" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 53 "Find the maximum \+ and minimum values of the function: " }{OLE 1 4185 1 "[xm]Br=WfoRrB::: wk;nyyI;G:;:j::>:B>N:F:nyyyyy]::yyyyyy:::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::::::::::::::fyyyyya:nYf::G:jy;::::::::::::: ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::JcvG YMt>^:fBWMtNHm=;:::::::n:;`:Z@[::JjpvpLu=XK[Aj;JZQZ:B :F:YLpfF>:::::::::J?NZ;vyyyyy=J:B:::::::c:;:=j[vGUMrvC?MoJ::::::::JCNZ ;F:f:vYxY:B::::::F:;jnJ:j;::::::::N<j>J?>:Q:SJ:f;;JAjA>:[Z:F:wAyA:::::: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::F:DJR<:TNEj`@Pt\\Pd`QrPPJPMQWdG_dnBwmcf]]:>::::::V:>::::::::::^=NZ:vn`AG>:^wgGC KYXM<;j;@j:HZDFZLVjBc:?fHDJ=q]<>kob>AFXHjAr<]R:?B\\_;Ob:GvDDk;aa=v;::b :K>da=v;::DKKDJ>U]LVJVir: yX:N:m_:>:C:?R:ElrfH=MtFGYMq>>Wlj:gmlJ::::::>^:NZ:vYxI:;J:<::::::C:C>; :?ja^G>d:NHEms>@[;;B:::::::JFNZ;V:;J:<:::::::::::::::::::vYxI:;Z::::::::j:f:Z:f:^[<>b<>^JV<l;B:;R:;b:x;B:U:_cZ;b::a=:J:C:[q:v [:>:_;^>F`=Fu=Vq=r:<:c:ob:c:qAB:>L;B:;R:D:ETWAEUMES;sNmMk xPpFZ:^:f?=JEBOMUUEuV:bU@k;PntH@Z\\wGHk\\:GdV=uTcUW_mBTj\\Pqk JJTNs@@JnjwRI?B;KVGPM;Lj;]arW:sJ: hj:@j:N:KfFD=Ob:CjOV_<^Z=HImu:l;:::J>Q=bXdq;^=:bF:N\\\\f_<^:gKUDJ^;yayI:Z:FZ:C:[q:: :::::::::::::::::::Z<>Z:B::::::::::2:" }}{PARA 0 "" 0 "" {TEXT -1 32 " subject to the two constraints, " }{TEXT 256 1 " " }{OLE 1 4181 1 "[xm ]Br=WfoRrB:::wk;nyyI;G:;:j::>:B>N:F:nyyyyy]::yyyyyy::::::::::::::::::: ::::::::::::::::::::::::::::::::::::::::::::::::::::fyyyyya:nYf::G:jy; :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::JcvGYMt>^:fBWMtNHm=;:::::::n:;`:Z@[::JjpvpLu =XK[Aj;JZPZ:B:F:YLpfF>:::::::::J?NZ;vyyyyy=J:B:::::::c:;:=j[vGUMrvC?Mo J::::::::JCNZ;F:f:vYxY:B::::::F:;jnJ:j;::::::::N<:;:wyyN::wyyyq<:v:j>J?>:Q:S:UJ:n;v;;JBB:]:_J:V<^::::::::::=Jyyy;d:yayYZHQ:>:;`:Z@o^?GhoGfnG gioGSZ:^bM?^?GH:Y:ETV:WCKaTMcDGLyVDurB:;::::::A:;::::::::::s:?B:IgsC<; :CSfMLdxp^J:VZ;FZ=b<=b>AFXHjAr<]R:?B\\_;Ob:GvDDk;aa=v;::DKKDk;ea::::::jysyAB:^:F:;jysy?:;:Grr:mW:N:uN:>:C:?R:f:FZ::::::;C:?B:yay=J:@>Z::::::::kJ;@j ;>:C:yayA:<::::::GB:^o=Z:::::::::::::yay=J:B:::::::::::::::::::jysy:>: <::::::::fc:><^;UTRZ_?Z:>DEZ:F[Z;>ZcTTUUSaEBWTSiEB_tUUURWE:=JZ:N`DZ:F:Z;b::a=:J:C:[q:^;;B:_;L;B:;R:D:ETWAEUMES;sNmMkxPpFZ:^:f?=JG;[S:UTRc=PpdPOL@j<@Z?BKaTMP]:V\\QGghGbHWdCS>EBOMUUEuV:bU@k;PntH@Z \\wGHk\\:GdV=uTcUW_mBTj\\PqkJJTNs@@JklbFN[<^Z@X?Qc:CrZmmvHZV:::b>?SE?B;AfXdQ;LZwRI?B;KFF<=QB:Z:FZ:C:[q:::::::::::: ::::::::::::::::::::::::::::::::::::::::::4:" }{TEXT -1 4 "and " } {OLE 1 4181 1 "[xm]Br=WfoRrB:::wk;nyyI;G:;:j::>:B>N:F:nyyyyy]::yyyyyy: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: fyyyyya:nYf::G:jy;:::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::JcvGYMt>^:fBWMtNHm=;:::::::n:;`:Z@[::JjpvpLu=XK[Aj;JZPZ:B:F:YLpfF>:::::::::J?NZ;vyyyyy=J:B:::::: :c:;:=j[vGUMrvC?MoJ::::::::JCNZ;F:f:vYxY:B::::::F:;jnJ:j; ::::::::N<:;:wyyN::wyyyq<:v:j>J?>:Q:S:UJ:n;v; ;JBB:]:_J:V<^::::::::::=Jyyy;d:yayYZHQ:>:;`:Z@o^?GhoGfnGgioGSZ:^bM?^?GH:Y:ETV:WCKaTMcDGLyVDurB:;::::::A:;::: :::::::s:?B:Igs;L:<:^aYHCcbiM<;j;@j:HZDFZLVjrs:YZEF\\;NZBP@N[kkZVHC>::::::vYxy;<:C:=J:vYxY;J:jt]:qe:nf=j:F;HjSA:?JGK: ^:NZ;jZ:>Z::::::J<>:s<;:?ja^G>D_mlVH[KRJ :<:::::::>=?R:AJ:^:vYxY:B::::::n:;JJI:<::::::::::::vYxI:;Z:::::::::::: ::::::::yay=J:B::::::::j`^;UTRZ_?Z:>DEZ:F[Z;>ZcTTUUSaEBWTSiEB_tUUURWE:=JL:::C:Uk:^:>x;B:O:_c:C:[q:N;N@B:?J:>iswu=r:<: c:QY:c:qi:Z:JB?Z:>Z;b:X;B:O:_cG;OS:UTRc=fdOo];fZ;R;Lncp^oB:arOMeU=dMaTL@k^@Oh[;^Z?gh];EDXceV=MC@lQPnAMnQ@NbLYBx j]xoZHni@>YVKciDyDLcy]=D:<[:_xIHby?cnA \\IFbdve>we?_xYgB@nAlj:F:=b:?b:?B:?j:@j:VZ;FZ:^:dj:A]k>Z:V[::^;yayI::sg:X=B:AB: " 0 "" {MPLTEXT 1 0 87 "c1 := x^2 + y^2 - z = 0: c2 := x^2 + 3 * y^2 = 1: H \+ := 5 * x^2 + y^2 + 5 * z^2-6 * z:\011" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "r := [x, y, z]:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "gH := Gradient(H, r);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 28 "gc1 := Gradient(lhs(c1), r);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 37 "Set up the three equations containing" }{MPLTEXT 0 21 1 " " }{XPPEDIT 18 0 "lambda[1];" "6#&%'lambdaG6#\"\"\"" }{TEXT -1 0 " " }{MPLTEXT 0 21 1 "." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 48 "eq := seq(gH[k] = lambda[1] * gc1[k], k = 1..3);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }{TEXT 259 0 "" }{TEXT -1 103 "Solve the system of \+ equations consisting of the constraint equation and the three equation s containing " }{XPPEDIT 18 0 "lambda[1];" "6#&%'lambdaG6#\"\"\"" } {TEXT -1 0 "" }{MPLTEXT 0 21 1 "." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 182 "Note how the use of backward quotes on the left of the assignment operator permits the creation of more suggestive notation. The subscr ipt selector must be placed outside the quotes." }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 47 "sol_1 := solve(\{eq, c1\}, \{x, y, z, lambda[1 ]\});" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 55 "Now we compute values of H for each of these solutions." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 46 "V1 := evalf(seq(subs(sol_ 1[k], H), k = 1..3));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 84 "We note a maximum value for H of 0 and a \+ minimum of -1.25. Compare the graphs of " }{XPPEDIT 18 0 "H^(-1);" "6#)%\"HG,$\"\"\"!\"\"" }{TEXT -1 4 "(0) " }{MPLTEXT 0 21 1 " " } {TEXT -1 3 "and" }{MPLTEXT 0 21 1 " " }{TEXT -1 0 "" }{XPPEDIT 18 0 "H ^(-1);" "6#)%\"HG,$\"\"\"!\"\"" }{TEXT -1 7 "(-1.25)" }{MPLTEXT 0 21 1 " " }{TEXT -1 21 "with the graph of c1." }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 120 "PH[0] := implicitplot3d(H = 0, x = -1..1, y = \n-1 .5..1.5, z = 0..2, numpoints = 2000, style=patchnogrid, shading=zhue): \n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 75 "Pc1 := plot3d(x^2+y^2 , x = -1..1, y = -1..1, color = red, style=wireframe):" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 54 "display(PH[0], Pc1, axes=framed, or ientation=[60,60]);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }{TEXT 260 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 305 "You will be able to c onvince yourself, by rotating the plot on the screen, that H is tangen t to c1 at its lowermost extreme. Nonetheless, this graph does not rep resent a solution to the optimization problem. There are many points o n c1 that yield larger values of H than 0. An obvious choice is [1, 1, 2]." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 31 "subs(\{x = 1, y = 1 , z = 2\}, H);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 405 "This is just one of many instances in which a solut ion to an equation is not necessarily the solution to the problem. Rem ember, we set up equations based on conditions the solution must meet. It's the \"if\" side of a proposition. If X is a solution then it wil l satisfy this equation. However, the \"only if\" side, \"If X is a so lution to the equation then it is a solution to the problem.\" may not be true. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 33 "Now the same thing for H = -1.25" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 128 "PH[-1.25] := implicitplot3d(H = -1.25, x = -1 ..1, y = \n-1.5..1.5, z = 0..2, numpoints = 2000, style=patchnogrid, s hading=zhue):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 60 "display( PH[-1.25], Pc1, axes=framed, orientation=[180,80] );" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 92 "Here the graph of H is tangent to the graph of \+ c1 at each end of the ovoid graph of H. This " }{TEXT 261 2 "is" } {TEXT -1 88 " a solution. There are no points on c1 that will make the value of H smaller than -1.25." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 54 "Now we turn our attention to optimizing H on c2 alone." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 28 "gc2 := Gradient(lhs(c2), r);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 32 "Set up the equations containing " }{XPPEDIT 18 0 "lambda[2];" "6#&%'lambdaG6#\"\"#" }{TEXT -1 1 "." }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "eq2 := seq(gH[k] = lambda[2] * gc2[k], k = 1..3);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 74 "Solve the system consisting of the constr aint and the equations containing" }{MPLTEXT 0 21 1 " " }{XPPEDIT 18 0 "lambda[2];" "6#&%'lambdaG6#\"\"#" }{TEXT -1 0 "" }{MPLTEXT 0 21 1 " ." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 48 "sol_2 := solve(\{eq2, \+ c2\}, \{x, y, z, lambda[2]\});" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 " " }}{PARA 0 "" 0 "" {TEXT -1 37 "Compute the value of H at each point. " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 46 "V2 := evalf(seq(subs(so l_2[k], H), k = 1..3));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 53 "Now we compare the plot of H = 3.2 to the plot of c2." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 116 "PH[3.2] := implicitplot3d(H = 3.2, x = -1..1, \ny = -1..1, z = 0..2, axes = fram ed, numpoints = 2000, color = blue):\n" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 3 "c2;" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 92 "Pc2 := implicitplot3d(c2, x \+ = -1..1, \ny = -1..1, z = 0..2, color = red, style = wireframe):\n" }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 37 "display(PH[3.2], Pc2, axes \+ = framed);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 206 "H is tangent to c2 at its outermost extreme. Again, this plot does not represent a solution to the optimization problem. It is certainly clear that many points on c2 will yield values for H larger than 3.2." }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 133 "PH[-1.466666667] := implicitplot3d(H = -1.466666667, x = -1.. 1, \ny = -1..1, z = 0..2, axes = boxed, numpoints = 2000, color = blue ):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 31 "display(PH[-1.46666 6667], Pc2);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 94 "Now the graph of \+ H fits just inside the graph of c2. This is a minimum. There is no le vel set" }{MPLTEXT 0 21 1 " " }{OLE 1 4181 1 "[xm]Br=WfoRrB:::wk;nyyI; G:;:j::>:B>N:F:nyyyyy]::yyyyyy:::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::::::fyyyyya:nYf::G:jy;::::::::::::::::::::: ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::JcvGYMt>^:fB WMtNHm=;:::::::n:;`:Z@[::JJeWrLu=XK[Aj;J:T:<:=ja^GE=; :::::::::N;?R:yyyyyy:>:<::::::JDJ:j:VBYmp>HYLkNG>::::::::N::::::::N<JyK?j?J@j@>:W:YJ:><:a:c:e:gJ:v:;`:Z@o^?GhoGfnGgioGSZ::RSPN]v;fb k;n_>WdG_dnBwmcf]]:>::::::V:>::::::::::^=wcA[;B:SWwo]:>:GKn>koQIER :PZ>WdGSGV\\QGghGbHWdCS>EBOMUUEuV;cMEuW;cNYUU=eU;R>ARKeuRSUTCEBaTXUeRY EUHk\\:GdV=uTcUW_mBTj\\PqkJJTNs@@J@lQPnAMnQ@NbLYBxj]x oZHni@>YVKciDyDLcy]=D:<[:_xIHby?cnA\\I Fbdve>we?_xYgB@nAlj:F:=b:?b:?B:?j:@j:VZ;F:CZDFZ:NZ>VjBCLAJHr<=R:=J;fB] mt^:N:yay=J:B::::::^: @[;;B:::::::JFNZ;V:;JJ:<:::::::: :::::::::::vYxI:;Z::::::::J=EKKpL;LJ>A]k>Z:N[<^Z<@?Kc:CrZ[E:[e:CbZMkNr Q=DN;J:::::vYxy;<:C:=J::nn?B:qe:Nc=j:F;HjLAZ:N:W>;J Z:FZ<< JZyIewyyyy;I;^;UTRZ_?:[ll;B:;R :;b:;B>cTTP@:nG=JZ:N`DJ:Z:F`:^q;f:^<;W:Uh:eB:VY;fyB:>l;Z ;b::::^:f?=J:_;_cnj;r:EB:^L=B:;R:DZJ:a=:J:C:[q:N;N@B:?J:>cjGb=r:EB:^B:>L;B:;R:DZJfboWFrNNfi_G=B:C: Uk:^:>X;B:MJ:N`DZ:F:[oB:a:t>:EuV:bU@;e =Z\\wGH;J]Zo[@:>^@SR:C:j\\jj:Y;Bw[j]BN_A[lDB:cYK:B>H^;kAQNteB:=b:?J;<:=j:VjB;>ZEF:N:Gf>?[>:;B:Ob:>?r Z[MrbZM;;j?<:G;Sjysy=Z:>:>\\:B:qQBv:;J:^q " 0 "" {MPLTEXT 1 0 28 "E := eliminate(\{c1, c2\}, z);" }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 64 "He re we have z in terms of x and y. Now we need y in terms of x." }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "solve(E[2, 1], y); " }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 81 "Th is gives two parameterizations which, together, cover the line of inte rsection." }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 72 "L1 := [t, 1/3 * sqrt(-3 * t^2 + 3), t^2 + (1/3 * sqrt(-3 * t^2 + 3))^2]:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 73 "L2 := [t, -1/ 3 * sqrt(-3 * t^2 + 3), t^2 + (1/3 * sqrt(-3 * t^2 + 3))^2]:" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 111 "Const := spacecurve(\{L2, L 1\}, t = -1..1, color = black, thickness = 3, numpoints = 1000, axes = framed):\nConst;" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 90 "Now we will \+ optimize H subject to both constraints. Set up the three equations co ntaining" }{MPLTEXT 0 21 1 " " }{XPPEDIT 18 0 "lambda[1];" "6#&%'lambd aG6#\"\"\"" }{TEXT -1 4 " and" }{MPLTEXT 0 21 1 " " }{XPPEDIT 18 0 "la mbda[2];" "6#&%'lambdaG6#\"\"#" }{TEXT -1 0 "" }{MPLTEXT 0 21 1 "." }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 77 "eq3 := seq(gH[k] = evalm(la mbda[1] * gc1[k] + lambda[2] * gc2[k]), k = 1..3);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 103 "Solve the system of five equations consisting of the two constraints and the three equ ations containing" }{MPLTEXT 0 21 1 " " }{XPPEDIT 18 0 "lambda[1];" "6 #&%'lambdaG6#\"\"\"" }{TEXT -1 4 " and" }{MPLTEXT 0 21 1 " " } {XPPEDIT 18 0 "lambda[2];" "6#&%'lambdaG6#\"\"#" }{TEXT -1 0 "" } {MPLTEXT 0 21 1 "." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 63 "sol_3 := solve(\{eq3, c1, c2\}, \{x, y, z, lambda[1], lambda[2]\});" }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 66 "He re are the values of H corresponding to each of these solutions." }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 46 "V3 := evalf(seq(subs(sol_3[k ], H), k = 1..4));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 41 "Since the largest value of H is 4 we plot" } {MPLTEXT 0 21 1 " " }{OLE 1 4173 1 "[xm]Br=WfoRrB:::wk;nyyI;G:;:j::>:B >N:F:nyyyyy]::yyyyyy:::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::fyyyyya:nYf::G:jy;::::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::::::::::::::::::::JcvGYMt>^:fBWMtNHm=;:: :::::n:;`:Z@[::JJeWrLu=XK[Aj;J:T:<:=ja^GE=;:::::::::N ;?R:yyyyyy:>:<::::::JDJ:j:VBYmp>HYLkNG>::::::::N::::::::N<JyK?j?J@j@>:W:YJ:><:a:c:e:gJ:v:;`:Z@o^?GhoGfnGgioGSZ::RSPN]v;fbk;n_>WdG_d nBwmcf]]:>::::::V:>::::::::::^=wcA[;B:sWtoM:KMFaXwfZ;R;Lncp^o jCXontpZtnc`^KfZNGgggfm?^Hgfq?^LwggGfh?ZKVZ?gh]_gc_fZVdsgg\\wgfs>E>Wlj:gmlB:;:::::JJZ:J;vCS=[LsfFaMR>@>Z:: ::::::kJ;@j;>:C:yayA:<::::::M:Gv:B::::::::::::jysy:>:<:::::::::::::::: :::vYxI:;Z::::::::J=EKKpL;LJ>A]k>Z:N[<^Z<@?Kc:CB\\cKTDJZZ@:;::: :jysyAB:^:F:;B:yayQ:r:GW::C:?R:=B:EJ:Z:f:^[<>b<>v>V<Z:>rymTyyy yYJM:eY:l;B:;R:;b:;B> cTTP@:nG=JZ:N`DZ:F:;B:]C:sW:E:cJJAj`EjD<:qQ:uI<:[V:R:D::::C: Uk:^:>x;B:SB:;B:_;Z=B:^B:>l;>:@ZG;]R:UTRc=PpdPo<@j<@Z?BKRGH^;kAQNteB:=b:?J;<:=j:J:hj:J;njLN>LZkJ::Q B:n>^;yayI: " 0 "" {MPLTEXT 1 0 122 "PH[4] := implicitplot3d( H = 4, x = -2..2, y = -2..2, \nz = -2..2, numpoints = 2000, color = tu rquoise, style = wireframe):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 37 "display(PH[4], Const, axes = framed);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 34 "This is the plot of the maximum H." }{MPLTEXT 0 21 1 " " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 135 "The sol_3 corresponding to \+ -2.050000001, is imaginary. The smallest value of H corresponding to a real solution is, -1.111111111. Plot" }{MPLTEXT 0 21 1 " " }{OLE 1 4681 1 "[xm]Br=WfoRrB:::wk;nyyI;G:;:j::>:B>N:F:nyyyyy]::yyyyyy:::::::: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::fyyyyya :nYf::G:I:wAyA:::::::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::NDYmq^H;C:ELq^H_mvJ::::::::gjb[OhnxZQNr;V:>j@Z:j:vCSmlJ::::::::::OJ;@jyyyyyI:;Z:::::::^<>:F :AlqfG[maNFO=;::::::::_J;@j:j<>:yayA:<::::::=J:FG>:VZ:vCj^nGGmq>:;:::: ::::_Z:vyyuy:>:<::::::AJ:^:;J:JyyI?:Jyyyyg:n:v:>:M:wAQ:S:UJ:n;v;;JB B:]:_J:V<^:;`:Z@o^?GhoGfnGgioGSZ::RSPN]v;fbk;n_>WdG_dnBwmcf]]:>::::::V:>: :::::::::^=wcab;JXaXw>Z:>:gKn>mcQIER:PZ>WdGSGV\\QGghGbHWdCS>EBOMUU EuV;cMEuW;cNYUU=eU;R>ARKeuRSUTCEBaTXUeRYEUHk\\:GdV=uTcUW_mBTj\\PqkJJTN s@@J@lQPnAMnQ@NbLYBxj]xoZHni@>YVKciDyDLcy]=D:<[:_xIHby?cnA\\IFbdve>we?_xYgB@nAlj:F:=b:?b:?B :?j:@j:VZ;F:CZDFZ:NZ>VjBCLAJHr<=R:=J;fB]mt ^:N:yay=J:B::::::^:Z:J;vCS=[LsfFaMR>@>Z::::::::kJ;@j;>:C:yayA:< ::::::OB:;JjI:<::::::::::::vYxI:;Z::::::::::::::::::::yay=J:B::::::::n jLN^gNZ>>kkRF;B:Ob:CbZKKNDJ<@rRF`<^Z;p?Wc:CRZ];::::::::F?M[apC>:::::jy syAB:^:F::^xFjwD:Gw:F:MZ=VT;J;^OrymTyyyyY:i:eY :^;UTRZ_?Z:>DEZ:F[Z:JBAZ:>Z;>Z<>ZJ^dcSS :JqF:C:US:F[:>Z:N`DZ:F:;B:]C:sW:E:cJJAj`EjD<:qQ:uI<:[V:R:D::::C:Uk:^:> x;B:q:_;L=B:;R:D:js::^: f?;JZ=B:^B:>l;>:@ZP]:V:<[=SJvk?_xdZID:<[:_X=tYK LBxjZdVJ:;r<=:?J=EKKB;J:?@rRb:CJ Q:];::::::::F?MK:V[:JMJ@vYxy:B:;:[B::C:[q:::::::::::::::::::::::::::::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::4:" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 145 "PH[-1.111111111] := implici tplot3d(H = -1.111111111, x = -1..1, \ny = -1..1, z = 0..1.5, numpoint s = 2000, color = turquoise, style = wireframe):\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 48 "display(Const, PH[-1.111111111], axes = fra med);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 34 "This is the plot of the \+ minimum H." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 199 "It is clear that r estriction of H by two constraints is the same as restriction by a sin gle constraint represented by the line of intersection of the two grap hs representing the constraint equations." }{MPLTEXT 0 21 1 " " }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 227 "The power and usefulness of Maple in presenting these plots is apparent. The question as to whether a \+ particular solution really represents a maximum or minimum is frequent ly answerable by inspection that can then be verified." }{MPLTEXT 0 21 1 "\011" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 0 "" }{TEXT 263 0 "" }} {PARA 0 "" 0 "" {TEXT 264 8 "Practice" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 120 "1.What are the radii of the largest and smallest sphere s, centered at the origin, \ntangent to the ellipse described by " } {OLE 1 4657 1 "[xm]Br=WfoRrB:::wk;nyyI;G:;:j::>:B>N:F:nyyyyy]::yyyyyy: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: fyyyyya:nYf::G:I:wAyA::::::::::::::::::::::::::::::::::::::::::::::::: ::::::::::::::::::::::::::::::NDYmq^H;C:ELq^H_mvJ::::::::gjb[OhnxZQNr;V:>r@Z:j:vCSmlJ::::::::::OJ;@jyyyyyY;jysy;Z: ::::::^<>:F:AlqfG[maNFO=;::::::::_J;vyyuy:>:<::::::=J:FG>:VZ:vCj^nGGmq >:;::::::::_:=:yay=;Z::::::j;>:CJ:>:nyyM;:nyyyYE:G:IZ:>;F;N;;JyK@j@>:W :YJ:><:a:c:e:gJ:v<>=F=N=nYvY:::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::::::=Z:;H:<: TNEj`@Pt\\Pd`QrPPJPMQ:gJn^yeQIER:PZ>WdGSGV\\QGghGbHWd CS>EBOMUUEuV;cMEuW;cNYUU=eU;R>ARKeuRSUTCEBaTXUeRYEUHk\\:GdV=uTcUW_mBTj \\PqkJJTNs@@J@lQPnAMnQ@NbLYBxj]xoZHni@>YVKciDyDLcy]=D:<[:_xIHby?cnA\\IFbdve>we?_xYgB@nAlj:F :=b:?b:?B:?j:@j:VZ;F:CZDFZ:NZ>Vj_SS?B;?FD\\L;Lj;MangB]mt^:N:yay=J:B::::::^:Z:J;vCS=[LsfFaMR>@>Z::::::::kJ ;@j;>:C:yayA:<::::::Q:Oy:B::::::::::::jysy:>:<:::::::::::::::::::vYxI: ;Z::::::::J;LJ;a\\cNZ>njwRI?B;?vPhO;LJ>Q]oNZ@Nj]sR?B;?vUxP;LJ;IamOZ>BD :NZ>Njc:?FElL;TJ;IART`P;LZhcU?B;?FD:Zc:l:yayQ:p=j:F;HJfA:?B:MP:jKV<^;UTRZ_?Z:>DEZ:F[f;NVe:qi:;fyB:>l;B:;R:;b:;B>cTTP@ JcJqF:C:US:>?N`DB::KSDqTGAuUaEDMCEaUTWEDMCEAuUa]WOZ;NaR?R:NKK?gN;J:Hj<<:c:ckDjw;;B:>L=B:@Z<:Ums::^:f?=JLJ:Hj<<:c:gg:c:qAB:>L;J:@Zx;F:MJ:N`DZ:F:;B:u[=FS;JMJ>Aj`@Pt\\@PpdPOx@j<@:L>P]:VfH :Dpqr>:G:<[=SJvk?cDr]\\IFBvExo\\RJZ:FZ:>\\:B:qQBv:>:sg::B>N:F:nyyyyy]::yyyyyy: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: fyyyyya:nYf::G:jy;:::::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::JcvGYMt>^:fBWMtNHm=;:::::::n:;`:Z@[::JjYxsLu=XK[Aj;JZM:<:=ja^GE=;:::::::::N;?R:yyyyyy:>:<::::::J DJ:j:VBYmp>HYLkNG>::::::::N ::::::::N<;F;N;;j?J@>:UJ:n;;j A>:[Z:FwsGC>:AR:=r:dj:Dk;U^:yayQ:>:npEJTD:Cr::;B:E:Sb:DJJejCB:Gc;YJHvyyuyEl rfH=MtFGYMq>>Wlj:gmlJ::::::>^:NZ:vYxI:;B:<::::::C:S<;:?ja^G>D_mlVH[KRJ :<:::::::>=?R:AJ:^:vYxY:B::::::n:nAB::::::::::::jysy:>:<:::::::::::::: :::::vYxI:;Z:::::::::UD:[Z:>ryM]yyyyYjd:GX:^;UTRZ_?Z:>DEZ:F[:qi:;fyB:>l;B:;R:;b::c:GlDjw;<:[n:>Z;b:<;VH::C:Uk:^:>x;B:U:_;L;J:@Z:C:[ q:^;;B:_cn\\;fc[_HRSeTOOR:ER:PZ>WdGSGARKeuR:Dpqr>E[[v_?wk>w_;?dnA\\IvbYGbJOxYn];?dni\\IFb:^x?_x_^xIPbYGB<[=we ;kAQNteli\\NtyrZnjwRI?B;KvGXM;Lj;]arOZ>njerD?B;KVGPM;Lj;aasOZ >nJj;eatk?:^;yayI::B>N:F:nyyyyy]::yyyyyy:::::::::::::::::::::::::::: :::::::::::::::::::::::::::::::::::::::::::fyyyyya:nYf::G:jy;::::::::: :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: JcvGYMt>^:fBWMtNHm=;:::::::n:;`:Z@[::JjYxsLu=XK[Aj;J: QZ:B:F:YLpfF>:::::::::J?NZ;vyyyyy=J:B:::::::c:;:=j[vGUMrvC?MoJ:::::::: JCNZ;F:f:vYxY:B::::::F:;jnJ:j;::::::::N<;;j>J?>:Q:S:UJ:n;;jA>:[Z:FwsGC>:AR:=r:dj:Dk;U^::::::: :jysyAB:^:F:;jysy?:;:=C<^`r:qX:N:g>;JfAV<:::::: ;C:?B:yay=J:D_mlVH[KRJ:<:::::::>=?R:AJ:^:vYxY:B: :::::n:>x=Z:::::::::::::yay=J:B:::::::::::::::::::jysy:>:<::::::::fc:> <Zl;F :;R:;b:isOIES:wR:sW:E :cJJAJ]fLR:D::::C:Uk:^:>x;B:MB:;B:_;B:>l;>:@ZX=J@JSd:>:_cX=j>JSd:Z:fFHJEC:G;?S:UTRc=PpdPOE@j<@Z? 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