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If A and B are acute angle such that SinA=8/17 and CosB=3/5.Find
1, Cos(A+B)
2, Sin(A+B)
3, Sin(A-B)

  • Math -

    draw triangles to see that

    cosA = 15/17
    sinB = 4/5

    now, use your angle sum formulas. What do you get?

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