SOLUTION: Find the soultion for sin^2x + 3sin - 1 = 0 in radian

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Question 810241: Find the soultion for sin^2x + 3sin - 1 = 0 in radian
Answer by lwsshak3(11628) About Me  (Show Source):
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Find the soultion for sin^2x + 3sin - 1 = 0 in radian
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sin^2x + 3sinx - 1 = 0
solve for sinx by quadratic formula:
sinx+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=3, c=-1
ans:
sinx=3.3028(reject,(-1 < sinx < 1)
or
sinx≈-0.3028
x≈3.4492, 5.9556 (in quadrants III and IV where sin<0)