- #1

- 64

- 0

## Homework Statement

## Homework Equations

## The Attempt at a Solution

Assume c\b is a subset of c\a. This means if x Є c Λ (Not Є) b, then it is an Є c Λ (Not Є) a.

Assume x Є c Λ (Not Є) b, but is Not Є c Λ (Not Є) a. Then x Є c Λ a. But this contradicts,

c\b is a subset of c\a. Therefore, a must be subset of b.