How do you calculate the cos[2sin1(12)]?

1 Answer
Feb 26, 2016

12

Explanation:

First, focus on just sin1(12). This is another way of asking, for what angle is sine equal to 1/2? Recall that

sin(π6)=12

Thus, since sin and arcsin are inverse functions,

sin1(12)=π6

Substitute this into the original expression:

cos[2sin1(12)]=cos(2π6)=cos(π3)=12