Question

Which of the following are correct?
I. $A-B=A-(A\cap B)$
II. $A=(A\cap B)\cup (A-B)$
III. $A-(B\cup C)=(A-B)\cup (A-C)$

• A. I and II
• B. II and III
• C. I, II and III
• D. None of these

Answer 1

Answer: (A)

I
It is clear from the Venn diagram
$A-B=A-(A\cap B)$
II. Also, it is clear from above diagram
$A=(A\cap B)\cup (A-B)$
III.
It is clear from the diagrams
$A-(B\cup C)=(A-B)\cap (A-C)$