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Question
If f : R → R, g : R → are given by f(x) = (x + 1)2 and g(x) = x2 + 1, then write the value of fog (−3).
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Solution
\[\left( fog \right)\left( - 3 \right) = f \left( g \left( - 3 \right) \right)\]
\[ = f\left( \left( - 3 \right)^2 + 1 \right)\]
\[ = f\left( 10 \right)\]
\[ = \left( 10 + 1 \right)^2 \]
\[ = 121\]
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