#1 read about casting out threes and casting out nines
#2 false. 1/0 is not defined
#3 since 7 is not even, what do you think?
Determine whether the following biconditional statements are true or false.
1. Any whole number is divisible by 3 if and only if the sum of its digits is divisible by 3.
2. 1/x > 0 if and only if x ≥ 0.
3. 2 is a prime if and only if 7 is even.
1 answer