SOLUTION: solve the equation -3 cos squared theta + sin theta = -3

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Question 678918: solve the equation
-3 cos squared theta + sin theta = -3

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
solve the equation
for interval:[0,2π]
-3 cos squared theta + sin theta = -3
-3cos^2x+sinx=-3
-3(1-sin^2x)+sinx=-3
-3+3sin^2x+sinx=-3
3sin^2x+sinx=0
sinx(3sinx+1)=0
sinx=0
x=0,π
or
(3sinx+1=0
3sinx=-1
sinx=-1/3
x=3.48, 5.94 (in quadrants III and IV where sin<0)