Find the constants given the domain and range

bcast

New member
Suppose you have a function y = f(x) such that the domain of f(x) is 1 ≤ x ≤ 6 and the range of f(x) is −3 ≤ y ≤ 5.

a) Find constants B and C so that the domain of f(B(x − C)) is 8 ≤ x ≤ 9
B=
C=

b) Find constants A and D so that the range of Af(x) + D is 0 ≤ y ≤ 1
A=
D=

I'm working on composition of functions and completely lost at this point.

MarkFL

Administrator
Staff member
Hello and welcome to MHB, bcast!

I have moved your topic from the Analysis forum as this is a Pre-calculus topic.

For the first problem, I would begin with the function's new domain:

$$\displaystyle 8\le x\le9$$

Now, assuming $B$ is positive, can you algebraically get $B(x-C)$ in the middle, and then equating the end-points to the originals, you will have two equations in two unknowns?