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Question
Let f, g: R → R be defined by f(x) = 2x + 1 and g(x) = x2 – 2, ∀ x ∈ R, respectively. Then, find gof
Solution
Given that, f(x) = 2x + 1 and g(x) = x2 – 2, ∀ x ∈ R
Then (gof)x = g(f(x)} = g(2x + 1) = (2x + 1)2 – 2
= 4x2 + 4x + 1 – 2
= 4x2 + 4x – 1
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