SOLUTION: Please help me with this equation: 2*cos^2(pi*x)- 5*cos(pi*x) +2 = 0

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Question 817306: Please help me with this equation:
2*cos^2(pi*x)- 5*cos(pi*x) +2 = 0
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
2*cos^2(pi*x)- 5*cos(pi*x) +2 = 0
2cos%5E2%28pix%29-5cos%28pix%29%2B2=0
solve for cos(πx)
for interval(0,2π)
factor:
(2cos(πx)-1)(cos(πx))-2)=0
..
2cos(πx)-1=0
cos(πx)=1/2
πx=π/3,5π/3
x=1/3,5/3
or
cos(πx)-2=0
cos(πx)=2
no solution: (-1 < cos(πx) < 1)