If $f (x) = x^{2} + 1$ $f(x)=x^2+1$ and $g (x) = x - 2$ $g(x)=x-2$ , how do you find f[g(x)]?

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Answer 1 · 2015-11-12T16:48:24

$f [g (x)] = {(x - 2)}^{2} + 1 = x^{2} - 4 x + 4 + 1 = x^{2} + 4 x + 5$ $f[g(x)]=(x-2)^2+1=x^2-4x+4+1=x^2+4x+5$

To calculate $f (g (x))$ $f(g(x))$ you have to replace every occurence of $x$ $x$ in $f (x)$ $f(x)$ with the formula of $g (x)$ $g(x)$

If f(x)=x^2+1f(x)=x2+1f(x)=x^2+1 and g(x)=x-2g(x)=x−2g(x)=x-2, how do you find f[g(x)]?