Question

If the sets $A$ and $B$ are as follows:
$A=\{1,2,3,4\},B=\{3,4,5,6\}$, then

• A. $A-B=\{1,2\}$
• B. $B-A=\{5,6\}$
• C. $[(A-B)-(B-A)]\cap A=\{1,2\}$
• D. $[(A-B)-(B-A)]\cup A=\{3,4\}$

Answer 1

Answer: (A), (B), (C)

The correct options are
A $B-A=\{5,6\}$
B $A-B=\{1,2\}$
C $[(A-B)-(B-A)]\cap A=\{1,2\}$

Given, $A=\{1,2,3,4\},B=\{3,4,5,6\}$
$\therefore A-B=\{1,2\};B-A=\{5,6\}$
$\left[\right(A-B)-(B-A\left)\right]\cap A=[\{1,2\}-\{5,6\}]\cap \{12,3,4,\}=\{1,2\}$