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Question
Let f : R → R be the function defined by f(x) = 4x − 3 for all x ∈ R Then write f . [NCERT EXEMPLAR]
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Solution
We have,
f : R → R is the function defined by f(x) = 4x −3 for all x ∈ R
\[y = 4x - 3\]
\[ \Rightarrow 4x = y + 3\]
\[ \Rightarrow x = \frac{y + 3}{4}\]
\[So, f^{- 1} \left( y \right) = \frac{y + 3}{4}\]
\[or, f^{- 1} \left( x \right) = \frac{x + 3}{4}\]
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