SOLUTION: Solve the equation and check for extraneous solutions. sqrt(2x^2-1)=x

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Question 39849: Solve the equation and check for extraneous solutions.
sqrt(2x^2-1)=x
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt(2x^2-1)=x
Square both sides to get:
2x^2-1=x^2
x^2-1=0
(x-1)(x+1)=0
x=1 or x=-1
Check these answers in the original equation.
x=-1 is extraneous because sqrt(1) is not -1; only -sqrt1=-1.
Cheers,
Stan H.