Let f(x) = 3x + 5 and g(x) = x - 4.
Find f o g and its domain
Answer choices
3x + 1; all real numbers
3x + 1; all real numbers except x = 4
3x - 7 ; all real numbers
3x - 17; all real numbers except x = 4

Question

Let f(x) = 3x + 5  and g(x) = x - 4.
Find f o g and its domain
Answer choices
		3x + 1; all real numbers
		3x + 1; all real numbers except x = 4 
		3x - 7 ; all real numbers
		3x - 17; all real numbers except x = 4

accessdenied · Answer

(f o g)(x) = f( g(x) ) = 3(x - 4) + 5
                             = 3x - 12 + 5
                             = 3x - 7

There are no restrictions on the domain with this function, so all real numbers are applicable.