How can you use trigonometric functions to simplify 21 e^( ( pi)/2 i ) into a non-exponential complex number?
1 Answer
Mar 3, 2016
Explanation:
There is this identity which is very useful.
r e^{i theta} = r (cos theta + i sin theta)
In this case,
r = 21
theta = pi/2
So plugging the values in
21 e^{i pi/2} = 21 (cos (pi/2) + i sin (pi/2))
= 21 ((0) + i (1))
= 21 i