SOLUTION: Solve the equation. (Use n as an integer constant. Enter your response in radians.) 100 cos2 x − 25 = 0

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Question 929091: Solve the equation. (Use n as an integer constant. Enter your response in radians.)
100 cos2 x − 25 = 0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
This is the difference of two squares.
100cos%5E2%28x%29-25=0
%2810cos%28x%29-5%29%2810cos%28x%29%2B5%29=0
Two solutions:
10cos%28x%29-5=0
10cos%28x%29=5
cos%28x%29=1%2F2
x=pi%2F3 and x=%285%2F3%29pi
and
10cos%28x%29%2B5=0
10cos%28x%29=-5
cos%28x%29=-1%2F2
x=%282%2F3%29pi and x=%284%2F3%29pi