Hello, I am new to the forum here and am not sure if I am posting this in the correct section. I didnt see any section for complex variables and this seemed the closest to complex analysis
I need help establishing the following identity
= + /
That is divided by . (I didnt know how to write that out in tex)
I need help establishing the above identity using DDe Moivre's formula and
Put in the identity and then take the real part of both sides. On the left, you get as required (by De Moivre's theorem). On the right, you want the real part of Rationalise the denominator of that fraction, by multiplying top and bottom of the fraction by Then take the real part and use some trig identities to get the answer in the required form.