Question

show that if ais A subset B,Then C-B is subset of C-A

Answer 1

First take this sets
A={1,2,3}
B={1,2,3,4,5}
C={1,2,3,4,5,6,7}
Here A⊂B
C-B={6,7}
C-A={4,5,6,7}
Hence C-B is ⊂ C-A

Answer 2

Answer:

Hence proved that $C-B$ is the subset of $C-A$ if A is a subset of B.

Solution:

Let us consider the sets of A, B and C as follows

A = {a, b, c}

B = {a, b, c, d, e}

C = {a, b, c, d, e, f, g}

So here, we are taking A as the subset of B and B is the subset of C.

∴ $C-B$ = {f,g}

∴ $C- A$ = {d,e,f,g}

Here, we can find that the $C-B$ contains the values of $C-A$ and $C-A$ has more values other than $C-B$

Hence we can prove that $(C-B)$ is the subset of $(C-A)$ if A is the subset of B.