Question

find the exact value sin(60°-45°)

Answer 1

60 - 45 = 15.
15 is half of 30, and you have the exact value for sin(30), so using the half angle formula you can find the exact value for sin(15)
(I had to look it up online - search for 'half angle formula' )

Answer 2

Or simply use
\[sin(A-B)=sinAcosB-cosAsinB\]45 and 60 are special angles, so, you can find the value without calculator easily.

Answer 3

ahh - yes that is simpler

Answer 4

The exact values of sin 60, sin 45, cos 60 and cos 45 can be found from these triangles: