Practicing Success
Practicing Success
CUET Preparation Today
Which of the following functions is inverse of itself in its domain? |
$f(x)=\frac{1-x}{1+x}$ $f(x)=5^{\log x}$ $f(x)=2^{x(x-1)}$ none of these |
$f(x)=\frac{1-x}{1+x}$ |
Since $fof(x)=f(f(x))=f\left(\frac{1-x}{1+x}\right)=\frac{1-\frac{1-x}{1+x}}{1+\frac{1-x}{1+x}}=x,∀\,x$ $∴ fof = I$ ⇒ f is the inverse of itself. |
