Question

Write the expression as the sine, cosine, or tangent of an angle.

cos 107° cos 42° + sin 107° sin 42°

Answer 1

sin 65°

cos 65°

cos 149°

sin 149°

Answer 2

@hartnn

Answer 3

use the formula
\(\Large \cos A\cos B + \sin A \sin B = \cos(A-B)\)

Answer 4

I got 65

Answer 5

so it would be cos65?

Answer 6

107-42 = 65
so, yes! cos 65 is correct :)