In my book and in other places, they give this rule to obtain the domain for(adsbygoogle = window.adsbygoogle || []).push({});

a compound function: "the domain of (f o g) (x) is the set of all real

numbers x such that g(x) is in the domain of f (x)."

Then, if f(x)=x^(1/4)

and

g(x)=x^2

f(g(x)) = (x^2)^(1/4)

f(g(x)) = x^(1/2)

And applying the rule for the domain, it'll be all the real numbers. Isn't it illogical?

Thanks for the help and excuse me if there is any grammar mistakes, it's because english isn't my native language.

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# About domain in a compound function

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