Question

what is the largest number that you need to test as a divisor to determine whether each of the following is prime : 1.40 2. 101 3. 7363​

Answer 1

Answer:

If both a and b were greater than the square root of n, a*b would be greater than n. So at least one of those factors must be less than or equal to the square root of n, and to check if n is prime, we only need to test for factors less than or equal to the square root.