How do you find the domain of $[fog](x)$ given $f(x)=5x$ and $g(x)=x^3$ ?

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Answer 1 · 2017-01-13T13:08:21

The domain is $=RR$

This is a composition of functions

$f(x)=5x$

$g(x)=x^3$

The domain of $f(x)$ is $D_f(x)=RR$

The domain of $g(x)$ is $D_g(x)=RR$

$(fog(x))=f(g(x))=f(x^3)=5x^3$

The domain of $fog(x)$ is $D_(fog(x))=RR$

How do you find the domain of [fog](x)[fog](x) given f(x)=5xf(x)=5x and g(x)=x^3g(x)=x^3?