{VERSION 4 0 "IBM INTEL NT" "4.0" } {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 1 } {CSTYLE "" -1 257 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 1 }{CSTYLE "" -1 258 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 262 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 263 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 265 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 267 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 268 "" 0 1 0 0 0 0 1 0 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 "" -1 276 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 277 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 278 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 279 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 280 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 281 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 282 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 283 "" 0 1 0 0 0 0 1 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 284 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 285 "" 0 1 0 0 0 0 1 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 286 "" 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 288 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 289 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 290 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 291 "" 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "Tim es" 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 "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 }{PSTYLE "Normal" -1 257 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 1 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 256 48 "MAT1154 \+ - Equa\347\365es Diferenciais e de Diferen\347as " }}{PARA 257 "" 0 " " {TEXT -1 31 "A equa\347\343o de diferen\347as linear." }{TEXT 257 0 "" }}{PARA 256 "" 0 "" {TEXT -1 3 "por" }}{PARA 256 "" 0 "" {TEXT -1 17 "George Svetlichny" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "res tart:" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 85 "Definimos a equa\347\343 o de diferen\347as linear y(n+1)=a(n)*y(n)+h(n) na linguagem do Maple. " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "eq:=y(n+1)=a(n)*y(n)+h( n);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 46 "A t\355tulo de exemplo, es colhemos o coeficiente " }{TEXT 262 4 "a(n)" }{TEXT -1 25 " e o termo \+ n\343o homog\352neo " }{TEXT 263 4 "h(n)" }{TEXT -1 1 "." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "a(n):=5;h(n):=2^n+1;" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 21 "Resolvemos a equa\347\343o." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "rsolve(eq,y(n));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 28 "Note a constante arbitr\341ria " }{TEXT 258 5 " y(0) " }{TEXT -1 117 "que aparece na resposta. O primeiro termo \351 a solu\347\343o geral da equa\347\343o homog\352nea, e o resto \351 uma solu\347\343o particular." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 39 "Vam os agora impor uma condi\347\343o inicial." }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 11 "ci:=y(0)=7;" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 46 "Resolvemos agora a edo com a condi\347\343o inicial." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "rsolve(\{eq,ci\},y(n));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 49 "Agora com um termo n\343o homog\352neo ma is complicado." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "h(n):=n^3 *exp(-2*n);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "rsolve(eq,y( n));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 12 "simplify(%);" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "h(n):=sin(n);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "rsolve(eq,y(n));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 12 "Vamos agora " }{TEXT 270 6 "apagar" }{TEXT -1 15 " as defini\347\365es " }{TEXT 265 4 "a(n)" }{TEXT -1 3 " e " } {TEXT 267 4 "h(n)" }{TEXT -1 31 " tornando-os de novo genericos." }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 34 "unassign('a(n)');unassign('h (n)');" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 30 "Resolvemos a equa\347 \343o gen\351rica." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "rsolv e(eq,y(n));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 76 "Esta \351 a formul a apresentado em sala de aula, numa forma um pouco diferente." }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 21 "Vamos agora escolher " }{TEXT 268 4 "a(n)" }{TEXT -1 37 " uma constante determinado, diagamos " }{TEXT 276 3 "5, " }{TEXT -1 1 "e" }{TEXT 277 6 " h(n) " }{TEXT -1 19 " de fo rma especial." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "a(n):=5;h( n):=n^2*2^n;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 16 "rsolve(eq,y (n));" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 275 "Note que o primeiro ter mo \351 solu\347\343o geral da equa\347\343o homog\352nea e o resto \+ \351 solu\347\343o particular. O segundo termo tamb\351m \351 uma solu \347\343o da equa\347\343o homog\352nea e portanto podemos considerar \+ os primeiros dois termos como uma outra express\343o para a solu\347 \343o geral da equa\347\343o homog\352nea." }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 12 "simplify(%);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 46 "Os tr\352s \372ltimos termos \351 um polin\363mio de grau " } {TEXT 278 1 "2" }{TEXT -1 7 " vezes " }{TEXT 279 3 "2^n" }{TEXT -1 61 " em conformidade com o m\351todo de coeficientes indeterminados." }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 78 "Vamos agora escolher um termo n \343o homog\352neo onde o fator exponencial tem base " }{TEXT 280 1 "5 " }{TEXT -1 19 ", o coeficiente de " }{TEXT 281 5 "y(n)." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 14 "h(n):=n^2*5^n;" }}}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 16 "rsolve(eq,y(n));" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 12 "simplify(%);" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 82 "Note agora que a solu\347\343o particular, (os tr\352s \372ltimos \+ termos) \351 polin\363mio de grau " }{TEXT 282 0 "" }{TEXT 283 1 "3" } {TEXT 284 0 "" }{TEXT 285 20 " sem termo constante" }{TEXT 286 0 "" } {TEXT -1 61 " em conformidade com o m\351todo de coeficientes indeterm inados." }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 68 "O seguinte problema ac ha a soma das quartas pot\352ncias dos primeiros " }{TEXT 288 1 "n" } {TEXT -1 10 " inteiros " }{TEXT 289 21 "y(n)=1^4+2^4+...+n^4." }{TEXT -1 27 " A equa\347\343o de diferen\347as \351 " }{TEXT 290 19 "y(n+1)= y(n)+(n+1)^4" }{TEXT -1 14 " e obviamente " }{TEXT 291 6 "y(1)=1" } {TEXT -1 1 "." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 39 "a(n):=1; h (n):=(n+1)^4; ci:=y(1)=1; eq;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 21 "rsolve(\{eq,ci\},y(n));" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 12 "simplify(%);" }}}}{MARK "0 0 1" 3 }{VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }