SOLUTION: Solve 4 cos^2 x − 3 = 0 for all x.

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Question 1205932: Solve 4 cos^2 x − 3 = 0 for all x.
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

+4cos%5E2%28+x+%29-+3+=+0 for all x
4cos%5E2%28+x+%29=+3
cos%5E2%28+x+%29=+3%2F4
cos%28+x+%29=+sqrt%283%2F4%29
cos%28+x+%29=+sqrt%283%29%2F2+ or cos%28+x+%29=+-sqrt%283%29%2F2

Solutions
x+=+cos%5E-1%28+sqrt%283%29%2F2%29
x+=+pi%2F6
general: x+=+pi%2An+-+pi%2F6, n element Z
or
x+=+cos%5E-1%28+-sqrt%283%29%2F2%29
x+=+5pi%2F6
general:+x+=+pi%2An+-+5pi%2F6, n+element Z