# trig

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3sin(2x)-2cos(x)=0

• trig -

Use the equation
sin(2x) = 2 sin x cos x
so that
6 sinx cosx -2 cosx = 0
cosx*(1 - 3sinx) = 0
(I divided out -2)

So the equation is satisfied wherever cosx = 0 or sinx = 1/3

x = pi/2 and 0.3398 radians are two solutions. There are others in other quadrants.

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