# Science talk:Math Exam Resources/Courses/MATH220/December 2010/Question 04 (b)

## Contents

Point out that B can be larger217:28, 29 April 2015

## Point out that B can be larger

I think the key point here is that B can/must be larger than A, and that the condition that ${\displaystyle g\circ f}$ is injective does not constrain us on the part of B that is not touched by f. With this intuition your counter-example comes out of nowhere.

06:57, 29 April 2015

Again not sure how you want to change the solution but I did fix the hint...

15:38, 29 April 2015

You just know how to rewrite hints :)

17:28, 29 April 2015