Question

For any two sets $M\&N,\text{if}M\subseteq N,$ then $M△N=$

• A. $N-M$
• B. $M-N$
• C. $\varnothing$

Answer 1

The correct option is A $N-M$

Given two sets $M\&N$ such that $M\subseteq N$
$\Rightarrow M△N=(M\cup N)-(N\cap M)$
$\because M\subseteq N$
$\Rightarrow M\cup N=N;N\cap M=M$
$\Rightarrow M△N=N-M$