Sum and Difference Identities

0

cos(40)cos(50)-sin(40)sin(50)

(√6-√2)/4

cos(5pi/12)

(√2)-√6)/4

cos(7pi/12)

-1

cos(87)cos(93)-sin(87)sin(93)

-√3/2

sin(40)cos(160)-cos(40)sin(160)

(√6+√2)/4

sin(75)

-2-√3

tan(7pi/12)