{VERSION 2 3 "SUN SPARC SOLARIS" "2.3" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "#Make Maple Lie" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "#Maple knows the quadratic f ormula" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "solve(a*x^2+b*x+c =0,x);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "#Maple knows the \+ cubic formula" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "solve(a*x^ 3+b*x^2+c*x+d=0,x);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "#Map le knows 4th degree equations " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "solve(a*x^4+b*x^3+c*x^2+d*x+e=0,x);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 91 "#The RootOf notation doesn't look like much gain, \+ but then the allvalues command tells more" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 46 "allvalues(solve(a*x^4+b*x^3+c*x^2+d*x+e=0,x));" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 57 "# 5th degree equations are i mpossible to solve in general" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 41 "solve(a*x^5+b*x^4+c*x^3+d*x^2+e*x+f=0,x);" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 52 "allvalues(solve(a*x^5+b*x^4+c*x^3+d*x^2+e*x+f= 0,x));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 47 "# particular 5th \+ degree equations can be solved" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "quintic:=x^5-x^3-1;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "solve(quintic);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "allv alues(solve(quintic));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 174 " # Note that maple includes the complex roots, 4 of the 5 roots are com plex. Often plotting the function gives a better idea (but it takes a \+ while to find the correct ranges.)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "plot(quintic,x=-2..2,y=-2..2);" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 151 "# Armed with this information, one can use th e numerical method fsolve(exp,var,range) to find a numerical approx to the root of exp in the range range." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 25 "fsolve(quintic=0,x,1..2);" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 57 "# Checking ranges without roots get the silent trea tment " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "fsolve(quintic=0, x,-1..1);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 81 "# another meth od for finding numerical answers is with evalf, (but we lose stuff)" } }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 24 "evalf(solve(quintic,x));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "#Problem 1 f(x)=x^3-6*x+1 " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 84 "#a. Show f has 3 real \+ roots by plotting the function and using fsolve to approx each" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 107 "#b. Explain why evalf(solve (f(x)=0,x)) cannot be the roots of a cubic equation (with integer coef ficients) " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "#c. Why did M aple make this error?" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "#P roblem 2 f(x)=exp(x)+sin(x)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 97 "#a Show f has infinitely many roots by plotting (well show enough \+ of the plot to see the pattern)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "#b How many roots does maple find? " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 57 "#c Use fsolve to find the 3 largest roots of e^x+s in(x)=0" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "#Problem 3 f(x)= sin(x)-cos(x);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 115 "#a Plot \+ both sin and cos for 0..2*Pi, by inspection write down the infinite fa mily of solutions to the roots of f. " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 44 "#b How many roots does Maple find to f(x)=0?" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 82 "#c There is a Maple variable _EnvAllSolutions, get maple to give your answer to a." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 99 "old:=_EnvAllSolutions;solve(sin(x)= 0);_EnvAllSolutions:=true;solve(sin(x)=0);_EnvAllSolutions:=old;" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "#Problem 4 Prove 2+2=5 with \+ Maple." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "# define a to be \+ 2 " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 10 "# add a+a;" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 "# define a to be 5/2 [on a s eparate line after the a+a)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 45 "# go back and execute the old a+a line again." }}}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 36 "# erase the line which makes a = 2.5" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 204 "#Problem 5 For the given f, find both x and y ranges which \"show\" all the features of the funct ion f \"nicely\". Features include zeros of f, f' and f'' and hence al l local extrema and points of inflection." }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 12 "#a f=xe^(-x)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 15 "#b f=x^2*exp(x)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 " " }}}}{MARK "46 0 0" 0 }{VIEWOPTS 1 1 0 1 1 1803 }