Which statements can easily be proved by a direct proof? If 5n+ 4 is even where n is an integer, then n is even. If n is odd, then n3 +1 is even. If n = (ab)2 where a and b are positive integers, then n 2 o2 and n 2 b2. If n is a perfect square where n is a positive integer, then n + 1 is not a perfect square.
Previous question
Next questio