The DeMoivres Theorem : if , then  .

The complex number is .

First convert the complex number into trigonometric form.

The trigonometric form is .

Let, .

Compare the complex number with a + ib.

a = 2 and b = 2.

The absolute value of z :

.

a = 2 > 0, so the angle is :

The trigonometric form of .

           (Using DeMoivres Theorem)

.

The result is .