Precalc with Trig

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What value(s) of x from 0 to 2pi solve the following equation: cos squared x - cos x - 6 = 0

  • Precalc with Trig -

    cos^2 - cos - 6 = 0
    (cos-3)(cos+2) = 0
    cos = 3 or -2
    Bzzzt. |cos| <= 1, so not possible.

    If there's a typo, fix it and apply the same steps.

  • Precalc with Trig -

    There isn't a typo this is the equation my professor gave us, thanks for the help!

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