In the contrapositive proof why does n 1 not being divisible

Last updated: 1/28/2023

In the contrapositive proof why does n 1 not being divisible by 4 mean that n is not divisible by 4 Consider n 4 for a counterexample 4 1 15 is not divisible by 4 but 42 must be divisible by 4 Using the note above what conclusions about n can you make from n 1 not being divisible by 4 Also why does n 1 not being divisible by 8 mean that n 1 must not be divisible by 4 There are integers that are not divisible by 8 but are divisible by 4 for example 12 Also can you think of any other remainders for n 1 if it is not divisible by 8 other than 1