SOLUTION: Solve each equation on the interval [0,2pi) sin^2x-cos^2x=0

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Question 1088052: Solve each equation on the interval [0,2pi)
sin^2x-cos^2x=0
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
To solve it effectively, you must to know that

sin%5E2%28x%29+-+cos%5E2%28x%29 = -cos(2x).


It is the direct consequence of the adding formula for cosine.


Then your equations becomes

cos(2x) = 0 

and has the solutions  x = pi%2F4, 3pi%2F4, 5pi%2F4 and 7pi%2F4.