SOLUTION: sin(x/2) + cos(x) = 0 Give all answers From 0 to 2pi

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Question 946034: sin(x/2) + cos(x) = 0
Give all answers
From 0 to 2pi
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
sin(x/2) + cos(x) = 0
Give all answers
From 0 to 2pi
***
sin%28x%2F2%29%2Bcosx=0
sqrt%28%281-cosx%29%2F2%29%2Bcosx=0
sqrt%28%281-cosx%29%2F2%29=-cosx
square both sides:
(1-cosx)/2=cos^2(x)
1-cosx=2cos^2(x)
2cos2(x)+cosx-1=0
(2cosx-1)(cosx+1)=0
..
2cosx-1=0
cosx=1/2
x=π/3,5π/3
or
cosx+1=0
cosx=-1
x=π