How do you evaluate e11π6ie15π8i using trigonometric functions?

1 Answer
Mar 30, 2017

The general equation is:

r1eθ1ir2eθ1i=r1cos(θ1)r2cos(θ2)+i(r1sin(θ1)r2sin(θ2))

Explanation:

You can derive the general equation, using Euler's Formula

eθi=cos(θ)+isin(θ)

reθi=rcos(θ)+i(rsin(θ))

For the given expression:

e11π6ie15π8i=cos(11π6)cos(15π8)+i(sin(11π6)sin(15π8))