Question

What is the exact value of cos(c + d), given sinc =24/25 for c in Quadrant II and cos d =-3/4 for d in Quadrant III?

-47/100

-1 3/100

21-24squareroot7/100
21
=24squareroot7/100

Answer 1

D.    $\frac{21 + 24\sqrt{7} }{100}$

Answer 2

Answer:

The other person is correct.