- #1

- 19

- 0

## Homework Statement

If h1 and h2 are contractions on a set B with contraction constants δ1 and δ2 prove that the composite function h2 ° h 1 is also a contraction on B and find a contraction constant.

## Homework Equations

|f(a) - f(b)| ≤ δ |a-b|

f '(c) = (f(a)-f(b))/(a-b)

(g°f) '(c) = g '(f(c))x f '(c)

## The Attempt at a Solution

So far I'm pretty sure i have to use the mean value theorem and the chain rule. using the mean value on the composite function i get :

|h

_{2}(h

_{1}(a)) - h

_{2}(h

_{1}(b))| = |h

_{2}°h

_{1})' (c)| |a-b|

i get stuck here, i think i should now use the chain rule for the derivaitve term out the front of the equality to somehow make an inequality. am i on the right track?

Last edited: