How do you find $(f o g) (12)$ $(fog)(12)$ given $f (x) = - 4 x + 2$ $f(x)=-4x+2$ and $g (x) = \sqrt{x - 8}$ $g(x)=sqrt(x-8)$ ?

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Answer 1 · 2017-03-29T08:56:38

The answer is $= - 6$ $=-6$

This a composition of functions

$f (x) = - 4 x + 2$ $f(x)=-4x+2$

$g (x) = \sqrt{x - 8}$ $g(x)=sqrt(x-8)$

$[f o g] (x) = f (g (x)) = f (\sqrt{x - 8})$ $[fog] (x)=f(g(x))=f(sqrt(x-8))$

$= - 4 \sqrt{x - 8} + 2$ $=-4sqrt(x-8)+2$

Therefore,

$[f o g] (12) = - 4 \sqrt{12 - 8} + 2$ $[fog] (12)=-4sqrt(12-8)+2$

$= - 4 \cdot 2 + 2$ $=-4*2+2$

$= - 6$ $=-6$

How do you find (fog)(12)(fog)(12) given f(x)=−4x+2f(x)=-4x+2 and g(x)=√x−8g(x)=sqrt(x-8)?