Let ABand X be sets Let ABand X be sets a Prove that if the
Let A,B,and X be sets
Let A,B,and X be sets a) Prove that if , then . Prove that if c) Suppose iff b) Prove that , thenSolution
a) A is contained in B means any element in A belongs to B
Thus x\\A means all elements in X- elements in A
is contained in All elements in X-elements in B obviously
Hence proved
A is contained in X.
Then x\\A means Elements in X not in A
X\\(x\\A) = elements in X and in A = A
Converse: given that
X\\(x\\A) = elements in X and in A = A
This implies
x/A = elements in X not in A
This implies A is contained in X
c) A is contained in X
Thus X\\A = X-A
X-A contains X-B
This implies that there are elements in A which are also in B
Thus each element inA belongs to B.
A is contained in B.
