Question

Using your knowledge of trigonometric identities, find the exact value of sin(x+y) knowing that x and y are between 0 and π2, that sin(x)=725 and that sec(y)=1312. Your answer must be a rational number, written in the form of an irreducible fraction p/q (such as 2/3, 4/5, −1/4, etc.), with q>0. Give the integers p and q.

Answer 1

Begin with:

sin(x+y) = sin(x)cos(y) + cos(x)sin(y)