Question

If A and B are positive acute angles, sin A=3/5, and cos B=12/13, what is the exact value of cos (A+B)

Answer 1

Do you know the identity for adding trig

Answer 2

cos A cos B-sin A sin B

Answer 3

yeah so we just use that

Answer 4

Do you know how by using right triangle you can figure Sin ,Cos

Answer 5

ok so (4/5)*(12/13)-(3/5)(5/13)