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Question
Find gof and fog, if f(x) = |x| and g(x) = |5x – 2|.
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Solution
f(x) = |x| and g(x) = |5x – 2|
∴ (gof)(x) = g(f(x))
= g(|x|)
= |5|x| – 2|
(fog)(x) = f(g(x))
= f(|5x – 2|)
= ||5x – 2||
= |5x – 2|
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