Question

f(x)=3/1-x,then find the value of f(f(x).

Answer 1

Hey there! Thanks for the question !

$f(x) = \frac{3}{1 - x} \\ f(f(x)) \\ = f( \frac{3}{1 - x} ) \\ = \frac{3}{1 - ( \frac{3}{1 - x} )} \\ = \frac{3}{ \frac{(1 - x) - 3}{1 - x} } \\ = \frac{3(1 - x)}{ - 2 - x} \\ = \frac{3(x - 1)}{x + 2} = \frac{3x - 3}{x + 2}$
f(f(x) = 3x-3 /x+2