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Consider f : R+ → [4, ∞) given by f(x) = x2 + 4. Show...

Consider f : R+ → [4, ∞ | Class 12 Mathematics Chapter Relations and Functions, Relations and Functions NCERT Solutions

Question:

Consider f : R₊ → [4, ∞) given by f(x) = x² + 4. Show that f is invertible with the inverse f^–1 of f given by , where R₊ is the set of all non-negative real numbers.

Answer:

f : R₊ → [4, ∞) is given as f(x) = x² + 4.

One-one:

Let f(x) = f(y).

∴ f is a one-one function.

Onto:

For y ∈ [4, ∞), let y = x² + 4.

Therefore, for any y ∈ R, there exists such that

∴ f is onto.

Thus, f is one-one and onto and therefore, f - 1 exists.

Let us define g: [4, ∞) → R+ by,

∴

Hence, f is invertible and the inverse of f is given by

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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 3 , Question 8: Consider f : R+ → [4, ∞) given by f(x) = x2 + 4. Show that f is invertible with the....

Consider f : R+ → [4, ∞ | Class 12 Mathematics Chapter Relations and Functions, Relations and Functions NCERT Solutions

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