Math (trig)

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4cos(x)+5=6sec(x)

  • Math (trig) -

    What about it? Are we solving for x ??

    if so, then ....
    4 cosx + 5 = 6/cosx
    4cos^2x + 5cosx = 6
    4cos^2x + 5cosx - 6 = 0
    (4cosx - 3)(cosx + 2) = 0
    cosx = 3/4 or cosx = -2 , Not possible since |cosx| ≤1
    so cosx = 3/4
    x = 41.4° or x = 221.4°

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