Q28

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Re: Q28

by wizardofwashington » Mon Sep 17, 2007 2:51 pm
magical cook wrote:Hi, Can anyone help with this? thank you.
I get an answer choice E = F(x) . Is that correct?

Here is the solution:
Substituting (-1/x) in the equation, you get:

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

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

Hope I got this one right. Correct me if I'm wrong. Thanks.
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by kajcha » Mon Sep 17, 2007 3:18 pm
Agree E

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by magical cook » Mon Sep 17, 2007 3:21 pm
Thank you yes, it's correct...but

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

I'm a bit cofused here..

from (1/x^2+1) / 1/x^2
Why not 1+ x^2 ? :?

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by kajcha » Mon Sep 17, 2007 3:29 pm
magical cook wrote:Thank you yes, it's correct...but

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

I'm a bit cofused here..

from (1/x^2+1) / 1/x^2
Why not 1+ x^2 ? :?
I think you interpreted it wrong. This stmt is like this

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

Hope this clears

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by magical cook » Mon Sep 17, 2007 3:34 pm
Oh, You're right - Thank you!