20 is the answer to the question you asked.
Answer:
Prove set equality by showing that for any element , if and only if .
Example:
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Step-by-step explanation:
Proof for for any element :
Assume that . Thus, and .
Since , either or (or both.)
- If , then combined with , .
- Similarly, if , then combined with , .
Thus, either or (or both.)
Therefore, as required.
Proof for :
Assume that . Thus, either or (or both.)
- If , then and . Notice that since the contrapositive of that statement, , is true. Therefore, and thus .
- Otherwise, if , then and . Similarly, implies . Therefore, .
Either way, .
Therefore, implies , as required.
the area of the triangle is 36
Answer:
193
Step-by-step explanation: