Answer: 90
Explanation:
To simplify the expression cos^(-1)(cos e) with e = -270°, we first need to find an equivalent angle in the range [0, 360) or [0, 2π]. Since -270° is -3/4 of a full rotation, we can find an equivalent angle by adding 360°:
e' = -270° + 360° = 90°
Now, we can evaluate the expression:
cos^(-1)(cos e) = cos^(-1)(cos 90°)
The cosine of 90° is 0:
cos(90°) = 0
Therefore, the expression simplifies to:
cos^(-1)(0) = 90
So, cos^(-1)(cos(-270°)) = 90.