SOLUTION: 3sin^2theta+7sintheta+4=0

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Question 1136705: 3sin^2theta+7sintheta+4=0
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

3sin%5E2%28theta%29%2B7sin%28theta%29%2B4=0 .......factor completely

3sin%5E2%28theta%29%2B3sin%28theta%29%2B4sin%28theta%29%2B4=0

%283sin%5E2%28theta%29%2B3sin%28theta%29%29%2B%284sin%28theta%29%2B4%29=0

3sin%28theta%29%28sin%28theta%29%2B1%29%2B4%28sin%28theta%29%2B1%29=0

%283sin%28theta%29%2B4%29%28sin%28theta%29%2B1%29=0

solutions:

%283sin%28theta%29%2B4%29=0 =>3sin%28theta%29=-4 =>sin%28theta%29=-4%2F3
=>there is no solution for theta that will make sin%28theta%29=-4%2F3 true
sin%28theta%29%2B1=0=>sin%28theta%29=-1
theta=+3pi%2F2+%2B2pi%2A+n will make sin%28theta%29=-1 true