Functions Question 112

Question: Function $ f:R\to R,\ f(x)=x^{2}+x $ is

[RPET 1999]

Options:

A) One-one onto

B) One-one into

C) Many-one onto

D) Many-one into

Show Answer

Answer:

Correct Answer: D

Solution:

$ \because f(0)=f(-1)=0 $ hence $ f(x) $ is many one. But there is no pre-image of $ -1 $ . Hence $ f(x) $ is into function. So function is many-one into.