Question

cos2x=1-3sinx equations for solutions

Answer 1

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Answer 2

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Formula to be used
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$= > \bf \: \cos(2x) = 1 - 2 \sin ^{2} (x)$
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$= > \bf \: \cos(2x) = 1 - 3 \sin( {x} ) \\ \\ or. \: \: 1 - 2 \sin ^{2} (x) = 1 - 3 \sin(x) \\ \\ or. \: \: 2 \sin ^{2} (x) - 3 \sin(x) = 0 \\ \\ or. \: \sin(x) (2 \sin(x) - 3) = 0 \\ \\ now \\ \bf \: \: since \: .. \: \sin(x) \leqslant 1...so \\ \\ = > \sin(x ) = 0 \\ \\ or. \: \sin(x) = \sin(n\pi) \\ \\ or. \: \bf \: x = n\pi... \\ \\ \bf \: where \: \: n = 0, 1, 2, 3, 4........so \: \: on$
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