Question

Which of the following functions from $Z$ to itself are bijections?

• A. $f\left(x\right)=x^3$
• B. $f\left(x\right)=x+2$
• C. $f\left(x\right)=2x+1$
• D. $f\left(x\right)=x^2+x$

Answer 1

The correct option is C $f\left(x\right)=2x+1$

z stands for integer

Bijction (or) bijection function means

a function whose co-domain matches

with range.

$\therefore f:R\to R,f\left(x\right)=x^3$

codomain : all real nos.

Range : $yϵR$

$f:R\to R$ $f\left(x\right)=x+2$

codomain : real nos

Range : $yϵR$

$f:R\to R$ $f\left(x\right)=2x+1$

codomain : Real nos

Range : $yϵR$

$f:R\to R$ $f\left(x\right)=x^2+x$

codomain : Real nos

Range : $yϵR$