Question

If sin A is equal to 3/5, cos B is equal to -12/13 and A is in 1st quadrant and B is in 3rd quadrant, find -
⇒ sin(A-B)
⇒ cos(A+B)
⇒ tan(A-B)

Answer 1

sinA=3/5,cosB=-12/13

sinB=-5/13,cosA=4/5

tanA=sinA/cosA=3/5÷4/5=3/4

tanB=sinB/cusB=-12/13÷-5/13=12/5

sin(A-B)=sinAcosB-cosAsinB