Sin (42) = cos (x)

Solve for x

X = 48

Step-by-step explanation:

When you type sin (42) in your calculator it will give you something around 0.669.

If you try reverse sinus sin-1 (0.669) it will give you 42.

Therefore you can say that:

Cos (x) = 0.669

So you can reverse the cos to get your answer

Cos-1 (0.669) = 48

Or

Cos-1 (sin (42))