Question

what is the inverse cosine of 0.55?
a. 0.57°
b. 56.6°
c. 55.0°
d. 33.4°

Explanation:

Step1: Use the inverse cosine function

Let \(x = \cos^{-1}(0.55)\). This means \(\cos(x)=0.55\).

Step2: Calculate using a calculator

Using a calculator in degree mode, \(x=\cos^{-1}(0.55)\approx56.6^{\circ}\)

Answer:

B. \(56.6^{\circ}\)