7 sin^2x - 14 sin x + 2 = -5 <--->
7*(sin^2(x) - 2sin(x) +1) = 0 <---->
= 0, <---->
sin(x) = 1 ---> x = , k = 0, +/-1, +/-2, . . .
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website! 7 sin^2 x - 14 sin x + 2 = -5
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subtract 2 from both sides of =
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7 sin^2 x - 14 sin x = -7
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divide both sides of = by 7
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sin^2 x - 2 sin x = -1
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sin^2 x - 2 sin x + 1 = 0
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factor the quadratic
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(sin x - 1)^2 = 0
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sin x = 1
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x = 90 + ( 2 * 180 * n) where n belongs to the integers(Z)
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