Question

HELP I JUST WANT TO KNOW IF IM CORRECT
Write the complex number in polar form. Express the argument in degrees. 4i

A. 4(cos 0° + i sin 0°)

B. 4(cos 270° + i sin 270°)

C. 4(cos 90° + i sin 90°)

D. 4(cos 180° + i sin 180°)

Answer 1

I PICKED C I'M CORRECT RIGHT?

Answer 2

4i = 0 + 4i ----> is the point (0,4) in the complex plane

r = 4 since (0,4) is 4 units from (0,0)

theta = 90 degrees (angle from positive x axis to terminal angle)


r*(cos(theta) + i*sin(theta))

4*(cos(90) + i*sin(90))

so you are correct, nice work

Answer 3

THANK YOU @jim_thompson5910

Answer 4

you're welcome