Pls help me~~

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by GmatMathPro » Thu Oct 06, 2011 6:23 pm
To evaluate F(-1/x), plug (-1/x) in for all instances of x in F(x):

F(x)=x^2+1/x^2

F(-1/x)=(-1/x)^2+1/((-1/x)^2)

=1/x^2+1/(1/x^2)

=1/x^2+x^2

=x^2+1/x^2

=F(x)

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