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Solve for x if sin2x=cos(x+60 and x€ [-90,180].show all work details

  • trig -

    What does x€ [-90,180] mean?
    The domain limits of x?

    You seem to have omitted a parenth after x+60

    cos(x+60) = sin(90-x-60)
    = sin (30-x)

    sin2x = sin(30-x)

    Therefore 2x = 30 -x
    x = 10 degrees is one solution

    See if you can find others. Note that sin2x = sin(180 -2x); that will lead to another solution.

  • trig -

    Yes it mean domaim limit of x that guied u when plot the graph

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