Chapter 5 Section 1 Composite Functions Worksheet
(Attach this sheet to your homework and turn in on the due date by the end of class)
Note: The odd problems are checked for completion. The one even problem will be
graded. The homework is worth 10 points. 5 points – completed, 5 – points graded
problem.
ALEKs: Take the Initial Assessment Test. (Because you are in a new class you have to
take it again.)
24
Homework: page 247 #7, 9, 15, 21,
, 25, 35, 41, 43, 45, 47, 65, 71
Definition: Given two functions f and g, the composite function, denoted f o g (read as f
composed with g), is defined by: (f o g)(x) = f(g(x)). The domain of f o g is the set of all
numbers x in the domain of g such that g(x) is in the domain of f.
Let f ( x)  x 2  4 and let g ( x)  2 x  5 .
1. Find (f o g)(2)
2. (g o f) (2)
3. (f o f)(-1)
4. A general expression for (f o g)(x).
5. The domain of f o g.
1
4
and let g ( x) 
x2
x 1
1. Find the domain of f o g
2. Find a general expression for f o g.
Let f ( x) 
Functions, besides described in equation format, can also be described in other formats.
Two such are tables and graphs. Problems 7-10 are of these type.
In class problems (As time allows) Page 247 #8, 10, 16, 26, 40, 46