trig

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how do you do sinAcosA=cosA-cos^3A/sinA

  • trig -

    divide each term by cosA
    sinA = 1 - cos^2A/sinA
    multiply each term by sinA
    sin^2A = sinA - cos^2A
    sin^2A = sinA - (1 - sin^2A)
    1 = sinA
    A = 90º or pi/2 radians

    or in general:
    A = k(90)º or k(pi/2) radians

  • trig -

    A = pi/2 + 2 n pi radians. n is any integer, including zero

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