SOLUTION: 3-5cosx+5sin^2x=0 solve for x

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Question 1137219: 3-5cosx+5sin^2x=0 solve for x
Answer by mananth(16946) About Me  (Show Source):
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3-5cosx+5sin^2x=0
sin^2x=(1-cos^2x)
Plug sin^2x
3-5cosx +5(1-cos^2x)=0
3-5cosx +5-5cos^2x =0
Rearrange
5cos^2x +5cosx -8=0
Solve the quadratic equation by formula method