SOLUTION: find sin(x+y) if sin x=2/3 and sin y= -1/3

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Question 958282: find sin(x+y) if sin x=2/3 and sin y= -1/3
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
This problem cannot be solved without additional information. This is so because
  • To find sin(x+y) we will use the identity:
    sin(x+y) = sin(x)cos(y) + cos(x)sin(y)
  • The identity requires cos(x) and cos(y).
  • But without information telling us the quadrant in which x and y terminate, we cannot find these cos's.