SOLUTION: sin2x+cosx=0 I thought that because there was sin2x; this meant I had to use sin x(2cosx-1)=0 sinx =0, 180; 2cosx-1=0 cosx =1/2= 60, 300 However; the answer is speci

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Question 957001: sin2x+cosx=0
I thought that because there was sin2x; this meant I had to use sin x(2cosx-1)=0
sinx =0, 180;
2cosx-1=0
cosx =1/2= 60, 300
However; the answer is specified as being 90,210, 270, 330
Where I have gone wrong

Answer by macston(5194)   (Show Source): You can put this solution on YOUR website!
sin(2x)+cos(x)=0
2sin(x)cos(x)+cos(x)=0

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