- #1
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Homework Statement
Show [tex]|sin z|^2 = \frac{1}{2}[cosh(2y)-cos(2x)][/tex]
Homework Equations
[tex]cosh2y = cosh^2y+sinh^2y[/tex]
[tex]cos2x = cos^2x-sin^2x[/tex]
The Attempt at a Solution
Here is what I have so far
[tex]|sinz|^2=|sin(x+iy)|^2=|sin(x)cosh(y)+icos(x)sinh(y)|^2[/tex]
[tex]=sin^2(x)cosh^2(y)+cos^2(x)sinh^2(y)[/tex]
[tex]=sin^2(x)cosh^2(y)+cos^2(x)sinh^2(y)-sin^2(x)sinh^2(y)+sin^2(x)sinh^2(y)[/tex]
[tex]=sin^2(x)[cosh^2(y)+sinh^2(y)]+sinh^2(y)[cos^2(x)-sin^2(x)][/tex]
[tex]=sin^2(x)cosh(2y)+sinh^2(y)cos(2x)[/tex]
how should i proceed?