[Date Index] [Thread Index] [Author Index]
Re: ComplexExpand off by a factor of (-1)?
On 2/22/13 at 1:05 AM, charles.ces at gmail.com wrote: >Would someone be able to help me understand why when I enter the >expression: >ComplexExpand[(E^(I*y) - E^(-I*y))/2*I] I get a result of -Sin[y] >instead of Sin[y]? You get -Sin[y] because that is the correct answer. You probably intended In:= ComplexExpand[(E^(I*y) - E^(-I*y))/(2*I)] Out= Sin[y] that is divide by 2 I rather than divide by 2 and *multiply* by I as you did. And since 1/I = -1 you got the correct result