SOLUTION: Find each value if sin A = 12/13 with 90 degrees <= A <= 270 degrees and if sin B = -7/25 with -90 degrees <= B <= 90 degrees. 1. sin(A + B)

Algebra ->  Trigonometry-basics -> SOLUTION: Find each value if sin A = 12/13 with 90 degrees <= A <= 270 degrees and if sin B = -7/25 with -90 degrees <= B <= 90 degrees. 1. sin(A + B)      Log On


   



Question 969488: Find each value if sin A = 12/13 with 90 degrees <= A <= 270 degrees and if sin B = -7/25 with -90 degrees <= B <= 90 degrees.
1. sin(A + B)

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Find each value if sin A = 12/13 with 90 degrees <= A <= 270 degrees and if sin B = -7/25 with -90 degrees <= B <= 90 degrees.
1. sin(A + B)
***
sinA=12/13 (90 < A < 270)
cosA=-5/13
..
sinB=-7/25 (-90 < B < 90)
cosB=24/25
sin(A+B)=sinAcosB+cosAsinB=12/13*24/25+-5/13*-7/25=288/325+35/325=323/325
..
Check:
sinA=12/13 (Q2)
A≈112.62
sinB=-7/25 (Q4)
B≈343.74
A+B=456.36
sin(A+B)=sin(456.36)≈0.9938
exact value as computed=323/325≈0.9938