Question

6. If fis a real function defined by f(x)= X-1 X+1 , then prove that : f(2x) = 3f(x)+1 f(x) +- 3 cy1

JEE/Engineering Exams

Maths

Solution

158

1.5 (2 ratings)

( f(x)=frac{x-1}{x+1} ) ( f(2 x)=frac{2 x-1}{2 x+1} ) ( begin{aligned} frac{1}{4 x+3}=& frac{3left(frac{x-1}{x+1}right)+1}{frac{x-1}{x+1}+3} &=frac{4 x-2}{4 x+2}=frac{2 x-1}{2 x+1}=frac{3 x-3+x+1}{x-1+3 x+3} end{aligned} )