Given the functions f(x) = (x + 2)/9 and g(x) = x^3 + 6, find fg(x).
Firstly, fg(x) could be written as f[g(x)], or in other words, the function f acts on the result of x going through the function g (Bear in mind that I'm using the square brackets only because it's easier to see). Hence, we could write fg(x) as f(x3 + 6). This is the same as writing [(x3 + 6) + 2]/9 because you're applying the function f to (x3 + 6) instead of just x. So this would give a final answer of fg(x) = [(x3 + 6) + 2]/9.
JJ
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