# Homework Help: Simple question on SET THEORY

1. Jan 17, 2012

### bernvall

1. The problem statement, all variables and given/known data

if A is a subset of B, then Bc \ C is a subset of Ac \ C for any set C

2. Relevant equations

A is a subset of B = for all elements in A are also elements in B

A\B = the complement of a set B in a set A
A\B= A and Bc

3. The attempt at a solution
I tried opening it up but i still couldnt find a solution

2. Jan 17, 2012

### micromass

Try to prove the contraposition: if x is not an element of $A^c\setminus C$, then x is not an element of $B^c\setminus C$.