Question

If f(x)=2x and g(x)=/x, what is the domain of (f o g)(x)? A) x=>0 B) x=0 C)x=<0 D) all real numbers

Answer 1

Answer:

Domain is $x\geq 0$

Step-by-step explanation:

$f(x)= 2x$

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

Now find (fog)(x)

$(fog)(x)= f(g(x))$

Plug in square root (x) for g(x)

$(fog)(x)= f(g(x))=f(\sqrt{x})$

Now we plug in sqrt(x) for x in f(x)

$(fog)(x)= f(g(x))=f(\sqrt{x})=2\sqrt{x}$

To find out the domain , we find the domain of 2square root (x)

To find domain of square root function , we set x>=0

Domain is $x\geq 0$

Answer 2

$f(x)=2x,\ g(x)=\sqrt{x}\\\\(f\circ g)(x)=2\sqrt{x}\\\\The\ domain:\\\\\boxed{x \geq 0}$