how do we write (A\l/A) \l/ (B\l/B ) in a much simpler form? (\l/= arrow pointing down)?

Answer 1

not((not A) or (not A)) or not ((not B) or (not B))
=not(A) or not(B) <-- from your previous question
= A and B <-- deMorgan's

Answer 2

It depends on what application you're writing in. In MS Word, you can choose Insert > Symbol and find an arrow from the table, then paste the arrow where you need it. If an arrow like this ↓ is what you want, you can also, in Word, type 2193, and then press Alt-X.

(A↓A) ↓ (B↓B )

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