Functions Problem

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Functions Problem

by mdwolman » Fri Jan 14, 2011 3:38 am
Hi all, this came up on my practice CAT, not sure how to solve...

For which of the following functions f is f(x)=f(1-x) for all x?

a) f(x) = 1-x

b) f(x) = 1-x^2

c) f(x) = x^2-(1-x)^2

d) f(x) = x^2(1-x)^2

e) f(x) = x/1-x

Thanks!

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by arora007 » Fri Jan 14, 2011 3:55 am
the answer should be D.

replace the x with 1-x in the given choices, if the value remains the same it should be the answer.


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

now after replacement of x to (1-x)

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

= (1-x)^2(x)^x
=f(x)
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by jaymw » Fri Jan 14, 2011 4:00 am
Please use the search function before posting a question.

https://www.beatthegmat.com/for-which-of ... 52991.html

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by Rahul@gurome » Fri Jan 14, 2011 7:21 am
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