# 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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