Functions Question 494

Question: If $ f:R\to R,f(x)= \begin{cases} x| x |-4,x\in Q \\ x| x |-\sqrt{3},x\notin Q \\ \end{cases}, $ then $ f(x) $ is

Options:

A) Many to one and into

B) Many to one and onto

C) one to one and into

D) one to one and onto

Show Answer

Answer:

Correct Answer: D

Solution:

[d] $ f(2)=f( {3^{1/4}} )\Rightarrow $ many to one function And $ f(x)\ne -\sqrt{3}\forall x\in R\Rightarrow $ into function