Functions Question 401

Question: . If $ f:R\to R $ , then $ f(x)=\ |x| $ is

[RPET 2000]

Options:

A) One-one but not onto

B) Onto but not one-one

C) One-one and onto

D) None of these

Show Answer

Answer:

Correct Answer: D

Solution:

$ f(-1)=f(1)=1 $ ;
$ \therefore $ function is many-one function. Obviously, f is not onto so f is neither one-one nor onto.