# How can you use trigonometric functions to simplify  2 e^( ( 13 pi)/12 i )  into a non-exponential complex number?

Use $A {e}^{\theta i} = A \cos \left(\theta\right) + A \sin \left(\theta\right) i$
$A {e}^{\theta i} = A \cos \left(\theta\right) + A \sin \left(\theta\right) i$
$2 {e}^{\frac{13 \pi}{12} i} = 2 \cos \left(\frac{13 \pi}{12}\right) + 2 \sin \left(\frac{13 \pi}{12}\right) i$