Relations Question 12

Question: A function F(x) satisfies the functional equation $ x^{2}F(x)+F(1-x)=2x-x^{4} $ for all real x. F(x) must be

Options:

A) $ x^{2} $

B) $ 1-x^{2} $

C) $ 1+x^{2} $

D) $ x^{2}+x+1 $

Show Answer

Answer:

Correct Answer: C

Solution:

$ x^{2}F(x)+F(1-x)=2x-x^{4} $ …(1)

Replacing $ x $ by $ 1-x, $ we get $ {{(1-x)}^{2}}F(1-x)+F(x)=2(1-x)-{{(1-x)}^{4}} $ …(2)

Eliminating $ F(1-x) $ from (1) and (2), we get $ F(x)=1-x^{2}. $