Question

The complex number -5i has the complex trigonometric form of 5(cos 270° + isin 270)

Answer 1

True , -5i = 5*(0 - i) = 5*( cos 3π/2 + i*sin 3π/2) = 5*(cos 270 + i*sin 270)

Explanation:

5*( cos 3π/2 radians + i*sin 3π/2 radians) = 5*(cos 270 degrees + i*sin 270 degrees)