Question

Identify the function from the given options?

• A. (i)
• B. (ii)&(iii)
• C. (iii)
• D. (iii) & (iv)

Answer 1

The correct option is D

(iii) & (iv)

Lets see the relation $f\left(x\right)=x^5$
For $x=-1$ the value of the relaiton is f (-1) = -1, but there is no -1 in the second set. So this expression is not a function.

Lets see the relation $f\left(x\right)=\pm \sqrt{x}$
For $x=4$ the value of the relation is f(4) = $\pm$ 2, in a function, an element will be mapped to only one element. So, this relation is not a function as 4 is mapped to both 2 and -2.

Lets see the relation $f\left(x\right)=\sqrt{x}$
For $x=-1$ the value of the relation f(-1) is not defined, therefore this relation is not a function.

Lets see the relation $f\left(x\right)=x^2$
All the values of x are mapped to only one value in the second set , therefore this relation is a function.
Hence the option with function $f\left(x\right)=x^2$ is the answer.