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

Let f : R → R be defined as f(x) = | Class 12 Mathematics Chapter Relations and Functions, Relations and Functions NCERT Solutions

Question:

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

(A) f is one-one onto

(B) f is many-one onto

(D) f is neither one-one nor onto.

Answer:

f: R → R defined as f(x) = 3x.

Let x, y ∈ 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.

∴f is onto.

Hence, function f is one-one and onto.

The correct answer is A.

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Welcome to the NCERT Solutions for Class 12 Mathematics - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 12: Let f : R → R be defined as f(x) = 3x. Choose the correct answer. (A) f is one-one onto (....

Let f : R → R be defined as f(x) = | Class 12 Mathematics Chapter Relations and Functions, Relations and Functions NCERT Solutions

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