Angle Sum and Differences Identities

Question 1

sin(A+B)

Answer 1

sin(A)cos(B) + cos(A)sin(B)

Question 2

sin(A–B)

Answer 2

sin(A)cos(B) – cos(A)sin(B)

Question 3

cos(A+B)

Answer 3

cos(A)cos(B) – sin(A)sin(B)

Question 4

cos(A–B)

Answer 4

cos(A)cos(B) + sin(A)sin(B)

Question 5

tan(A+B)

Answer 5

tan(A) + tan(B) OVER 1 – tan(A)tan(B)

Question 6

tan(A–B)

Answer 6

tan(A) – tan(B) OVER 1 + tan(A)tan(B)