Inverse sines and cosines: Without using a calculator, evaluate or simplify the following expressions. cos?1 ( )

Step-by-step solution Step 1 We need to evaluate cos ( ) without using a calculator. 2 Step 2 1 To evaluate the equation, we must find the angle x in which cos x is equal to 2, as shown below: x = cos 1 ( )1 2 cos x = 1 2