MCQ
Function $f:R \to R,\;f(x) = {x^2} + x$ is
  • A
    One-one onto
  • B
    One-one into
  • C
    Many-one onto
  • Many-one into

Answer

Correct option: D.
Many-one into
d
(d) $\because f(0)=f(-1)=0$

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.

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