{VERSION 6 0 "IBM INTEL NT" "6.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "" -1 256 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 257 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 259 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 260 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 261 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 262 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 263 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 264 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 265 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 266 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 267 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 268 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 269 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 270 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 271 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 } {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 "Text Output" -1 2 1 {CSTYLE "" -1 -1 "Courier" 1 10 0 0 255 1 0 0 0 0 0 1 3 0 3 0 }1 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Warning" 2 7 1 {CSTYLE "" -1 -1 "" 0 1 0 0 255 1 0 0 0 0 0 0 1 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Maple Output" -1 11 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }3 3 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Maple Outpu t" -1 12 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 } 1 3 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Maple Plot" -1 13 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 }{PSTYLE "Normal" -1 256 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 1 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 13 "Math 156 F'05" }}{PARA 256 "" 0 "" {TEXT -1 5 "Lab 2" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 265 20 "Derivatives in Maple" }{TEXT -1 7 " " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 29 "If f is a function of x then " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 257 12 "diff(f (x),x)" }{TEXT -1 76 " is the derivative applied to an expressin and producing an expression " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 258 4 "D(f)" }{TEXT -1 76 " is the derivative applied to a function and producing a function." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 102 "Example: Use Maple to f ind the critical points and inflection points for f(x) = x^3 +12*x^2 - 3*x +15" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "f:= x->x^3 + 12 *x^2 -3*x +15;" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 13 "plot(f(x),x);" }}{PARA 13 "" 1 "" {TEXT -1 0 " " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 49 "We can get a better view by s witching the domain " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "plo t(f(x),x=-20..6);" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 109 "There are critical points around 8 and around 0 \+ and an inflection point around 4. Let's get the exact values" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 14 "with(student);" }}{PARA 12 " " 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 17 "df:=diff(f(x),x);" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "fsolve(df=0,x);" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 30 "Those are the critical points." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "dd f:=diff(df,x);" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 46 "The second derivative can also be computed by " } {TEXT 256 15 "diff(f(x),x$2);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "diff(f(x),x$2);" } }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "fsolve(ddf=0,x);" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 29 "This i s the inflection point." }}}{EXCHG {PARA 0 "" 0 "" {TEXT 261 12 "Assig nment 1" }{TEXT -1 28 " Let g(x)=x^4-6x^3+1. " }}{PARA 0 "" 0 " " {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 259 3 "1A)" }{TEXT -1 90 " \+ Plot the graph of g(x) choosing the domain so that one can see all t he local minima." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 262 4 "1B) " }{TEXT -1 106 " Find the critical points of g( x) by computing the derivative of g(x) and solve the equation g'(x)=0 " }{TEXT 263 1 "." }{TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 260 5 "1C) " } {TEXT -1 85 "Find the minimum value of g(x) by checking the values of g at the critical points. " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT 264 3 "1D)" }{TEXT -1 191 " Find all inflection points of g(x) by solving the equation g''(x)=0. Check on the plotted graph that this coincides with the places that the graph changes from concave upwards to concave" }}{PARA 0 "" 0 " " {TEXT -1 26 "downwards (or vice versa)." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 266 12 "Riemann Sums " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 82 "Examp le: Use Maple to study the Riemann sums for f(x) = x^2 on the interva l [1,3]" }}{PARA 0 "" 0 "" {TEXT -1 1 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "restart; " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 14 "with(student);" }} {PARA 12 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 267 73 "The relevant Maple commands are leftbox, rightbox, leftsum and righsu m. " }}{PARA 0 "" 0 "" {TEXT -1 25 "For each you must specify" }} {PARA 0 "" 0 "" {TEXT -1 21 "1) the expression " }}{PARA 0 "" 0 "" {TEXT -1 24 "2) the domain x=a..b" }}{PARA 0 "" 0 "" {TEXT -1 33 " t3) he number of subIntervals " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 12 "f:= x->x^2;\n" }{TEXT -1 0 " " }}{PARA 0 "" 0 "" {TEXT -1 67 "We can see the Riemann boxes using le ft endpoints and 10 intervals." }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 24 "leftbox(f(x),x=1..3,10);" }} {PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 90 " It is clear that the area of the Riemann boxes underestimates the area under the curve. " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 49 "Next we s ee the boxes using right hand endpoints." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 25 "rightbox(f(x),x=1..3,10);" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 59 "It is clear that this t ime the boxes overestimate the area." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 79 "Let's now do the same example with shor ter subintervals. This time we use n=50" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "\nleftbox(f(x),x=1..3,50);\n" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "rightbox(f(x),x=1..3,50);\n" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 91 "It is nice to see both boxes at one time. For this we give the pictures names and use \+ the " }{TEXT 268 7 "display" }{TEXT -1 22 " command, which needs " } {TEXT 269 11 "with(plots)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 62 "left:=leftbox(f(x),x=1..3,10):right:=rightbox(f(x),x=1..3,10):" }} }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 12 "with(plots);" }}{PARA 7 "" 1 "" {TEXT -1 50 "Warning, the name changecoords has been redefined\n " }}{PARA 12 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "display(left,right);" }}{PARA 13 "" 1 "" {TEXT -1 0 " " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 35 "Do it again with more subinte rvals." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 64 "left2:=leftbox(f( x),x=1..3,50):right2:=rightbox(f(x),x=1..3,50):" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "display(left2,right2); " }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 52 "You can see that the boxes are now better estimates." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 34 "Let 's do the numbers for Example 1" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 11 "" 1 "" {TEXT -1 0 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 42 "L10:=leftsum(f(x),x=1.. 3,10): evalf(L10);\n" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 43 "R10:=rightsum(f(x),x=1..3,10): eval f(R10);\n" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 155 "Since f(x) is increasing on [1,3] the true answer is bet ween L10 and R10. This is not yet a very accurate approximation. We \+ will try again with larger n." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 48 "L1000:=leftsum(f(x),x=1..3,1000): evalf(L1000);\n" }}{PARA 11 " " 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 49 "R100 0:=rightsum(f(x),x=1..3,1000): evalf(R1000);\n" }}{PARA 11 "" 1 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 124 "To get accuracy \+ of four decimal places we would have to use n= 160,000. This is a slo w way to make accurate approximations." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT 271 17 "Assignment P art 2" }{TEXT -1 36 " Consider the function f(x) = 1/x." }}{PARA 0 " " 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 95 "2A) Graph the rig ht and left hand sums for the interval [1,2] with n=2,4,8,16,32 subint ervals." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 61 "2B) Compute the left and right hand sums at those intervals." }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 66 "2C) How accurate are the estimates you get with 32 subintervals?" }}{PARA 0 " " 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 270 17 "Assignment Part 3 " }{TEXT -1 38 " Repeat 2 with g(x) = x^4 on [-1,2]." }}}}{MARK "30 \+ 0 0" 70 }{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }