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how can i find a general solution of g(x)when they give me g(X) =cos (x+30)and g(X)= -2sinx

  • maths -

    well, when does

    cos(x+30) = -2sinx
    √3/2 cosx - 1/2 sinx = -2sinx
    √3/2 cosx = -3/2 sinx
    tanx = -1/√3
    since tan30 = 1/√3,
    x = (180-30) or (360-30) = 150 or 330
    or, more generally,

    x = 180n-30 for any integer n

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