# Function Composition

• Feb 12th 2008, 01:24 PM
Mortifix
Function Composition
I am stuck on this problem. Let f(x)=sqrt(1-x) and g(x)=sqrt(x-1). Determine (fog)(x). Thanks for the help (Bow)
• Feb 12th 2008, 01:32 PM
Jhevon
Quote:

Originally Posted by Mortifix
I am stuck on this problem. Let f(x)=sqrt(1-x) and g(x)=sqrt(x-1). Determine (fog)(x). Thanks for the help (Bow)

$(f \circ g)(x)$ means $f(g(x))$. that is, you plug in the function g for x in the function f.

so, $f(g(x)) = \sqrt{1 - (g(x))} = \cdots$ ?
• Feb 12th 2008, 01:42 PM
Mortifix
So $
f(g(x)) = \sqrt{1 - \sqrt{x-1}} =$
?
• Feb 12th 2008, 01:51 PM
Jhevon
Quote:

Originally Posted by Mortifix
So $
f(g(x)) = \sqrt{1 - \sqrt{x-1}} =$
?

yes