In each of following, determine whether statement is true or false. If it is true, prove it. If it i

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1.Set Theory

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In each of the following, determine whether the statement is true or false. If it is true, prove it. If it is false, give an example.

If $x \in A$ and $A \in B,$ then $x \in B$

Option A

Option B

Option C

Option D

Solution

False

Let $A=\{1,2\}$ and $B=\{1,\{1,2\},\{3\}\}$

Now, $2 \in\{1,2\}$ and $\{1,2\}$ $\in\{\{3\}, 1,\{1,2\}\}$

$\therefore A \in B$

Howerer, $2 \notin\{\{3\}, 1,\{1,2\}\}$

Standard 11

Mathematics

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