Question 928621: Find all solutions of the equation 3 sin^2 x -7 sin x + 2 = 0 in the interval [0,2pi).Help would truly be appreciated!
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Find all solutions of the equation 3 sin^2 x -7 sin x + 2 = 0 in the interval [0,2pi).
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Sub u for sin(x)
3u^2 - 7u + 2 = 0
Solve the quadratic, sub back sin(x) for u.
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(3u - 1)*(u - 2) = 0
u = 2, 1/3
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Sub back
sin(x) = 2 (reject, > 1)
sin(x) = 1/3
x =~0.33984 radians
x =~ 2.802 radians
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