pre cal 2

Find all solutions in the unterval [0,2pi), cos x/2-sinx=0

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asked by denise
  1. from sin2A = 2sinAcosA we can say that
    sinx = 2sin(x/2)cos(x/2)

    cos(x/2) = 2sin(x/2)cos(x/2)
    1= 2sin(x/2)
    sin(x/2) = 1/2
    x/2 = 30°, 150° or π/6, 5π/6 radians
    x = 60°, 300° or π/3, 5π/3 radians

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    posted by Reiny

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