For the real-valued functions f(x)=sqrt(5x+20) and g(x)=x-2 , find the composition f o g(x) and specify its domain using interval notation.

Question

For the real-valued functions f(x)=sqrt(5x+20)  and g(x)=x-2 , find the composition f o g(x) and specify its domain using interval notation.

anonymous · Answer

f(g(x) = sqrt(5(x-2)+20)
         = sqrt(5x-10+20)
         = sqrt(5x+10)

5x+10>=0 since sqrt cannot contain negative numbers

so 5x>-10
       x>-2

so domain is [-2,infinite) and range [0,infinte)

anonymous · Answer

f(x)=sqrt(5x-10)

anonymous · Answer

Would domain be [2,infinity) ?

anonymous · Answer

It is from [-2,infinity), can you please be clear with your question

anonymous · Answer

Find the domain of the function f(x)=sqrt(5x-10) 

I typed f(x)=sqrt(5x+10) in the first question. Sorry for the confusion.