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Question
Let f, g : R → R be defined by f(x) = 2x + l and g(x) = x2−2 for all x
∈ R, respectively. Then, find gof. [NCERT EXEMPLAR]
Solution
We have ,
f, g : R → R are defined by f(x) = 2x + l and g(x) = x2
−2 for all x
∈ R, respectively
\[Now, \]
\[gof\left( x \right) = g\left( f\left( x \right) \right)\]
\[ = g\left( 2x + 1 \right)\]
\[ = \left( 2x + 1 \right)^2 - 2\]
\[ = 4 x^2 + 4x + 1 - 2\]
\[ = 4 x^2 + 4x - 1\]
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