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Q. Write cosx and sinx in terms of e^ix and e^-ix respectively

So I wrote that cosx=Re(e^ix)=Re(e^-ix)

and sinx =Im(e^ix) and -Im(e^ix)

I think the above identites are correct, now I must use this to show that

16cos^3(x)sin^2(x) = 2cosx - cos3x - cos5x

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# Using e^ix to determine a trig identity

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