Use a sum or difference formula to find the exact value of the following. sin 5 pi/7 cos pi/28 + cos 5 pi/7 sin pi/28

## Answer

CoS +cos sin 1 28 2 20π + π = sin 1 28 ( 21st 28) 1 1 /2

Use a sum or difference formula to find the exact value of the following. sin 5 pi/7 cos pi/28 + cos 5 pi/7 sin pi/28

CoS +cos sin 1 28 2 20π + π = sin 1 28 ( 21st 28) 1 1 /2