Question

solve the question ( Isc )

Answer 1

can you pls say me what is    f:R =  R

so that i can answer this

Answer 2

$f(x) = \frac{2x}{2x^2+1}$

now 
$f(f(x)) = \frac{2f(x)}{2f(x)^2+1} = \frac{\frac{4x}{2x^2+1} }{2(\frac{2x}{2x^2+1} )^2+1}$

put x = 0.5
$f( \frac{1}{2} ) = \frac{2}{3}$

$f(f( \frac{1}{2} )) = f( \frac{2}{3} ) = \frac{4/3}{8/9+1} = \frac{12}{17}$