Question

Pre-calculus Help Please! Express the complex number in trigonometric form.

3

A. 3(cos 0° + i sin 0°)
B. 3(cos 90° + i sin 90°)
C. 3(cos 180° + i sin 180°)
D. 3(cos 270° + i sin 270°)

Answer 1

we have that

3 = 3 + 0i -----------> rewrite as 3(1 + 0i)

So now what we have to do is figure out which of the above expressions has cos a = 1 and sin a = 0.
cos 0 = 1, and sin 0 = 0, so that's the answer that we want.

the answer is:
3 = 3(cos 0 + i sin 0)