{VERSION 5 0 "SUN SPARC SOLARIS" "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 Output" 2 20 "" 0 1 0 0 255 1 0 0 0 0 0 0 0 0 0 1 } {PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Maple Output" 0 11 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 }3 3 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 0 "" 0 "" {TEXT -1 29 "**** MAPLE FILE #2 * ***" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 44 "Th is file explores how limits work in MAPLE." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 30 "**** Limits in MAPLE ****" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 80 "Suppose we have a funct ion f(x) and we want to find its limit at a number x = c." }}{PARA 0 " " 0 "" {TEXT -1 229 "One way to get an idea of whether such a limit ex ists and find its value is to \nevaluate the function repeatedly at po ints which approach c. An easy way to do\nthis using MAPLE is to const ruct a \"do loop.\"\n \nConsider the function:" }}}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 14 " y := sin(x)/x;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%\"yG*&-%$sinG6#%\" xG\"\"\"F)!\"\"" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 85 "Below, a do lo op is used to investigate this limit. First, let's consider values of \+ x" }}{PARA 0 "" 0 "" {TEXT -1 31 "that approach 0 from the right:" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 21 "for n from 1 to 15 do" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 26 " evalf(subs(x=1/n,y));" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 5 "od;\n " }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+[)4ZT)!# 5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+s2^)e*!#5" }}{PARA 11 "" 1 " " {XPPMATH 20 "6#$\"+/4%e\")*!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$ \"+s$eh*)*!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+SlYL**!#5" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+izw`**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+'3@g'**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+s 'yR(**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+llVz**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+l;M$)**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+'eJi)**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+W*H%))**!# 5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+%)49!***!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+o()\\\"***!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6 #$\"+SUf#***!#5" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 1 " " }}{PARA 0 " " 0 "" {TEXT -1 85 "What we did above was to plug into the function x= 1, x=1/2, x=1/3, ... , x=1/15, i.e." }}{PARA 0 "" 0 "" {TEXT -1 90 "nu mbers getting closer and closer to zero from the right. Note that ther e is no semi-colon" }}{PARA 0 "" 0 "" {TEXT -1 49 "after the \"do\" ab ove. The \"od\" ends the do loop. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }} {PARA 0 "" 0 "" {TEXT -1 86 "It seems that these values are approachin g 1. Try it now for values of x approaching " }}{PARA 0 "" 0 "" {TEXT -1 20 "zero from the left:\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "for n from 1 to 15 do" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 35 " evalf(subs(x=-1/n,y)); " }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 3 "od;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+[)4ZT)!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+s2^)e*!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+/4%e\")*!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+ s$eh*)*!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+SlYL**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+izw`**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+'3@g'**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+s'yR(**!#5 " }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+llVz**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+l;M$)**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+' eJi)**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+W*H%))**!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+%)49!***!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+o()\\\"***!#5" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$ \"+SUf#***!#5" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 84 "Notice that thes e values are precisely the same. That's because sin(x)/x is an even " }}{PARA 0 "" 0 "" {TEXT -1 51 "function (being the quotient of two odd functions)." }}{PARA 0 "" 0 "" {TEXT -1 50 "We therefore conclude tha t the limit we seek is 1." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 " " 0 "" {TEXT -1 74 "Actually MAPLE has a command that allows you to ca lculate limits directly." }}{PARA 0 "" 0 "" {TEXT -1 71 "Below, the li mit we deduced above is found using the \"limit\" command: \n" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "limit(y,x=0);" }}{PARA 11 " " 1 "" {XPPMATH 20 "6#\"\"\"" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 75 "C onveniently, MAPLE can even handle limits at infinity and infinite lim its." }}{PARA 0 "" 0 "" {TEXT -1 44 "The following examples indicate t he syntax:\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 9 "g := 1/x;" } }{PARA 11 "" 1 "" {XPPMATH 20 "6#>%\"gG*&\"\"\"F&%\"xG!\"\"" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "limit(g,x=infinity);" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#\"\"!" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 84 "This tells us that the graph of g(x) = 1/x has the x-axis as a horizontal asymptote." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 90 "What happens if we try to compute the limit of \+ 1/x at 0, where the function is unbounded?\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "limit(g,x=0);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6 #%*undefinedG" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 81 "As we will in cl ass, MAPLE also distinguishes between a limit like the one above " }} {PARA 0 "" 0 "" {TEXT -1 77 "(which is infinity from the right and -in finity from the left) and one like:\n" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 17 "limit(1/x^2,x=0);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6# %)infinityG" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 68 "The difference is \+ that the above limit is +infinity from both sides." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 89 "Finally, you can compute \+ one-sided limits by adding an optional third argument: right for" }} {PARA 0 "" 0 "" {TEXT -1 79 "a one-sided limit from the right, and lef t for a one-sided limit from the left:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "limit(g ,x=0,right);" }}{PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}{PARA 11 "" 1 " " {XPPMATH 20 "6#%)infinityG" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 18 "limit(g,x=0,left);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,$%)infini tyG!\"\"" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}}{MARK "23 \+ 0 0" 0 }{VIEWOPTS 1 1 0 3 2 1804 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }