SOLUTION: please help me solve this equation cosx + sqrt 3sinx = -1

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Question 1113281: please help me solve this equation cosx + sqrt 3sinx = -1

Found 2 solutions by Alan3354, greenestamps:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Isolate the radical, square both sides.
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"Please help me..." = do this for me so I don't have to learn how.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


cosx+%2B+sqrt+%283sinx%29+=+-1

sqrt%283sinx%29+=+-1-cosx

The left hand side is a square root, so it has to be 0 or positive.

The range of cosx is from -1 to 1; that means the range of the right hand side is from -2 to 0.

The right hand side is must be 0; that means cosx has to be -1.

sinx is 0 (and so sqrt(3sinx) is 0) when cosx is -1; so the equation is satisfied whenever cosx is -1, and ONLY then.

In the interval 0 to 2pi, the only solution is x=pi.

The complete solution is x = pi plus any (positive or negative) multiple of 2pi.