Explanation: 
Another Explanation (5):
দেওয়া আছে, \( f(x) = (1-x)^{-1} \)
সুতরাং, \( f(f(x)) = f((1-x)^{-1}) \)
এখন, \( f(f(x)) = \left(1 - (1-x)^{-1}\right)^{-1} \)
=\( \left(1 - \frac{1}{1-x}\right)^{-1} \)
=\( \left(\frac{1-x-1}{1-x}\right)^{-1} \)
=\( \left(\frac{-x}{1-x}\right)^{-1} \)
=\( \frac{1-x}{-x} \)
=\( \frac{-(x-1)}{-x} \)
=\( \frac{x-1}{x} \)
অতএব, \( f(f(x)) = \frac{x-1}{x} \) 🎉