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Trig Equation: Please Help (1 Viewer)

kazemagic

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Feb 8, 2012
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626
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HSC
2014
2sin^2x+cosx=2
2(1-cos^2x)+cosx=2
2-2cos^2x+cosx=2
0=2cos^2x-cosx
0=cosx(2cosx-1)
Therefore
0=cosx or 1/2=cosx

Then you should be able to do the rest
 

Timske

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Nov 23, 2011
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2012
Uni Grad
2016
2sin^2x + cosx = 2
2(1 - cos^2x) + cosx = 2
2 - 2cos^2x + cosx - 2 = 0
2cos^2x - cosx = 0
cosx(2cosx - 1) = 0
cosx = 0 and cosx = 1/2
 

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