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Re: ComplexExpand off by a factor of (1)?
Posted:
Feb 23, 2013 7:01 AM


On 2/22/13 at 1:05 AM, charles.ces@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[4]:= ComplexExpand[(E^(I*y)  E^(I*y))/(2*I)]
Out[4]= 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



