fg(x) means f(g(x)). Do g first, then put that answer into f.
Example: f(x) = 2x + 1, g(x) = x - 3
fg(x) = f(g(x)) = f(x - 3) = 2(x - 3) + 1 = 2x - 6 + 1 = 2x - 5
gf(x) = g(f(x)) = g(2x + 1) = (2x + 1) - 3 = 2x - 2
Note: fg(x) is usually not equal to gf(x).
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Given f(x) = x + 4, g(x) = 3x, h(x) = x2:Find fg(x)Find gf(x)Find fh(x)Find hf(2)Find gg(x)
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