"Consider the function f : R - { 2 / 3 } → R defined as f(x)= 4x + 3 / 6x - 4 which of the following is true about f "
Answer & explanation
Correct answer: option 4
$f(x)=\frac{4x + 3}{6x - 4}$
so $fof(x)=f(f(x))=\frac{4(\frac{4x + 3}{6x - 4})+3}{6(\frac{4x + 3}{6x - 4})-4}$
$=\frac{16x+12+18x-12}{24x+18-24x+16}$
$=x$