Question

If $A=\{1,2,4\},B=\{2,4,5\}$ and $C=\{2,5\}$, then $(A-B)\times (B-C)=$

• A. $\{(1,2),(1,5),(2,5)\}$
• B. $\left\{\{1,4\}\right\}$
• C. $(1,4)$
• D. $\left\{(1,2)\right\}$

Answer 1

The correct option is C $(1,4)$

$A=\{1,2,4\}$ and $B=\{2,4,5\}$

$A-B=\{1,2,4\}-\{2,4,5\}=\left\{1\right\}$

$B=\{2,4,5\}$ and $C=\{2,5\}$

$B-C=\{2,4,5\}-\{2,5\}=\left\{4\right\}$

$(A-B)\times (B-C)=\left\{1\right\}\times \left\{4\right\}=(1,4)$