{VERSION 2 3 "IBM INTEL NT" "2.3" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 }{CSTYLE "Hyperlink" -1 17 "" 0 1 0 128 128 1 0 0 1 0 0 0 0 0 0 } {CSTYLE "2D Comment" 2 18 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "2 D Output" 2 20 "" 0 1 0 0 255 1 0 0 0 0 0 0 0 0 0 }{CSTYLE "" 0 21 "" 0 1 0 0 0 1 0 0 0 0 2 0 0 0 0 }{CSTYLE "Help Heading" -1 26 "" 1 14 0 0 0 0 0 1 0 0 0 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 } {PSTYLE "Maple Output" 0 11 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 3 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Maple Plot" 0 13 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {SECT 0 {PARA 0 "" 0 "" {TEXT 26 8 "Advice: " }{TEXT -1 37 "Fr actional powers of negative numbers" }}{PARA 0 "" 0 "" {TEXT -1 0 "" } }{PARA 0 "" 0 "" {TEXT -1 175 "Maple's mathematics is largely based on complex numbers rather than real numbers. In particular, it uses the \"principal branch\" of fractional powers: the principal branch of " }{XPPEDIT 18 0 "z^(1/n)" ")%\"zG*&\"\"\"\"\"\"%\"nG!\"\"" }{TEXT -1 22 " has argument between " }{XPPEDIT 18 0 "-Pi/n" ",$*&%#PiG\"\"\"%\" nG!\"\"F'" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "Pi/n" "*&%#PiG\"\"\"%\" nG!\"\"" }{TEXT -1 22 ", and the argument of " }{XPPEDIT 18 0 "(-1)^(1 /n)" "),$\"\"\"!\"\"*&\"\"\"\"\"\"%\"nGF%" }{TEXT -1 4 " is " } {XPPEDIT 18 0 "Pi/n" "*&%#PiG\"\"\"%\"nG!\"\"" }{TEXT -1 17 ".\nSo for example:" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 18 "evalc((-1)^(1/5 ));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,(*$\"\"&#\"\"\"\"\"##F'\"\"%F) F'*(%\"IGF'F(F&,&F%F'F$!\"\"F&F)" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 9 "evalf(\");" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,&$\"+X* p,4)!#5\"\"\"%\"IG$\"+?D&y(eF&" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "evalf(argument(\")/Pi);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\" +)*******>!#5" }}}{PARA 0 "" 0 "" {TEXT -1 4 "The " }{MPLTEXT 0 21 4 " surd" }{TEXT -1 32 " function provides \"elementary\" " }{XPPEDIT 18 0 "n" "I\"nG6\"" }{TEXT -1 19 "'th roots, i.e. if " }{XPPEDIT 18 0 "x " "I\"xG6\"" }{TEXT -1 26 " is a negative number and " }{XPPEDIT 18 0 "n" "I\"nG6\"" }{TEXT -1 14 " is odd, then " }{MPLTEXT 0 21 9 "surd(x, n)" }{TEXT -1 24 " is the real (negative) " }{XPPEDIT 18 0 "n" "I\"nG6 \"" }{TEXT -1 12 "'th root of " }{XPPEDIT 18 0 "x" "I\"xG6\"" }{TEXT -1 1 "." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 11 "surd(-8,3);" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#!\"#" }}}{PARA 0 "" 0 "" {TEXT -1 149 "In order to have a somewhat nicer syntax, as well as covering rationa l exponents with numerators other than 1, I have defined an infix-form operator " }{MPLTEXT 0 21 2 "&^" }{TEXT -1 85 ". This is part of the Maple Advisor Database, and must be read in before being used:" }} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 14 "readlib(`&^`);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 27 "(-1)&^(2/5), (-1) &^ (3/5);" }} {PARA 11 "" 1 "" {XPPMATH 20 "6$\"\"\"!\"\"" }}}{PARA 0 "" 0 "" {TEXT -1 13 "For positive " }{XPPEDIT 18 0 "x" "I\"xG6\"" }{TEXT -1 2 ", " } {XPPEDIT 18 0 "x &^ p" "-%#&^G6$%\"xG%\"pG" }{TEXT -1 16 " is the same as " }{XPPEDIT 18 0 "x^p" ")%\"xG%\"pG" }{TEXT -1 16 ". For negative " }{XPPEDIT 18 0 "x" "I\"xG6\"" }{TEXT -1 5 ", if " }{XPPEDIT 18 0 "p =m/n" "/%\"pG*&%\"mG\"\"\"%\"nG!\"\"" }{TEXT -1 43 " is a fraction we have the following cases:" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 13 "assume(x<0); " }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 1 " " }{XPPEDIT 18 0 "m" "I\"mG6\"" }{TEXT -1 5 " and " }{XPPEDIT 18 0 "n" "I\"nG6\"" }{TEXT -1 11 " both odd: " }{XPPEDIT 18 0 "`&^`(x,(m/n)) = -(-x)^(m/n) ;" "/-%#&^G6$%\"xG*&%\"mG\"\"\"%\"nG!\"\",$),$F&F+*&F(F)F*F+F+" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 11 "x &^ (3/5);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#,$*$,$%#x|irG!\"\"#\"\"$\"\"&F'" }}}{EXCHG {PARA 0 "" 0 "" {XPPEDIT 18 0 "m" "I\"mG6\"" }{TEXT -1 7 " even, " } {XPPEDIT 18 0 "n" "I\"nG6\"" }{TEXT -1 6 " odd: " }{XPPEDIT 18 0 "`&^` (x,m/n) = (-x)^(m/n);" "/-%#&^G6$%\"xG*&%\"mG\"\"\"%\"nG!\"\"),$F&F+*& F(F)F*F+" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 11 "x &^ (4/5);" }} {PARA 11 "" 1 "" {XPPMATH 20 "6#*$,$%#x|irG!\"\"#\"\"%\"\"&" }}} {EXCHG {PARA 0 "" 0 "" {XPPEDIT 18 0 "m" "I\"mG6\"" }{TEXT -1 6 " odd, " }{XPPEDIT 18 0 "n" "I\"nG6\"" }{TEXT -1 7 " even: " }{XPPEDIT 18 0 "`&^`(x,(m/n));" "-%#&^G6$%\"xG*&%\"mG\"\"\"%\"nG!\"\"" }{TEXT -1 12 " is complex." }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 11 "x &^ (3/8); " }}{PARA 11 "" 1 "" {XPPMATH 20 "6#*&!\"\"#\"\"(\"\"),$%#x|irGF$#\"\" $F'" }}}{PARA 0 "" 0 "" {TEXT -1 5 "When " }{XPPEDIT 18 0 "x" "I\"xG6 \"" }{TEXT -1 30 " is not known to be real, and " }{XPPEDIT 18 0 "p" " I\"pG6\"" }{TEXT -1 16 " is a fraction, " }{XPPEDIT 18 0 "x&^p" "-%#&^ G6$%\"xG%\"pG" }{TEXT -1 87 " is written as a surd. When p is given i n decimal form, it is converted to a fraction." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 20 "x:= 'x': x &^ (3/8);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%%surdG6$*$%\"xG\"\"$\"\")" }}}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 11 "x &^ 0.375;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#-%%s urdG6$*$%\"xG\"\"$\"\")" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 " plot(x &^ (2/3), x = -1 .. 1);" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "plot(x &^ (3/5), x = -1 .. 1 );" }}{PARA 13 "" 1 "" {TEXT -1 0 "" }}}}{SECT 0 {PARA 0 "" 0 "" {TEXT 26 9 "See also:" }{TEXT -1 1 " " }{HYPERLNK 17 "^" 2 "^" "" } {TEXT -1 2 ", " }{HYPERLNK 17 "&^" 2 "&^" "" }{TEXT -1 2 ", " } {HYPERLNK 17 "surd" 2 "surd" "" }}}{SECT 0 {PARA 0 "" 0 "" {TEXT 26 24 "Maple Advisor Database " }{TEXT -1 15 "R. Israel, 1998" }}}} {MARK "2 0 0" 20 }{VIEWOPTS 1 1 0 1 1 1803 }