if n is a natural number , then 6 n ^ 2 + 6 n is always divisible by ?
"6 n ^ 2 + 6 n = 6 n ( n + 1 ) , which is always divisible by 6 and 12 both , since n ( n + 1 ) is always even . answer is b"
add(multiply(6, const_100), multiply(2, 6))