Originally Posted by

**Skeith** Hi guys,

Was hoping someone could help with this question - I'd appreciate it.

The question;

"Use a direct method of proof to show that if x and y are odd integers, then xy is also odd.

The given solution;

First, notice that if x is odd then x = 2m + 1 where m is an integer. Similarly,

y = 2n + 1 for some integer n. <- I understand up to this point.

Then get lost around here.

Then, xy = (2m + 1)(2n + 1) = 4mn + 2m + 2n + 1 = 2 (2mn + m + n) + 1 which is an odd integer."

Could someone explain what exactly is happening in that section?

Thankyou,

- Jamie.