You can solve this one easily with your calculator. BUT ... you can solve it even more easily with your brain.
If you ever hung around on a rainy day looking at a right triangle and thinking about sines and cosines, you probably noticed that the sine of any angle is the cosine of its complement, and the cosine of any angle is the sine of its complement.
The complement of 37° is 53° .
So the cos(37°) = the sin(53°).
