find f(x)

If and f is differentiable function satisfies :

then find f(x)

not a doubt....jus found it gud

6 Answers

anyone trying this??

no one [11]

Put y=x

f(x + (x+1)f(x) ) = x + (x+1)f(x)

=> f(x)=x , x + (x+1)f(x) = 0

@ dubey sir.....dat does not necessarily confirm f(x)=x is the only function satisfying it...

Also f(x)=-1 is another one satisfying this.

ok i m giving the ans

A small extension, division by k.f'(x) is valid only when f'(x) â‰ 0, f(x)=-1 is a valid soln in this case.

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