Q12 of 107 Page 10

Let f: R → R be defined as f (x) = 3x. Choose the correct answer.

It is given that f: R → R be defined as f (x) = 3x.

Let x, y ϵ R such that f(x) = f(y).


⇒ 3x = 3y


⇒ x = y


⇒ f is one–one.


Also, for any real number (y) in co–domain R, there exists in R such that



Therefore, f is onto.


Therefore, function f is one-one and onto.

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