Prove that is divisible by 7.
I set about trying to show that this expression is equal to .
I have that:
The question also has Fermat's little theorem above it so I think I should be using that somewhere.
Anyone have any ideas?
I finally got it to work out using TheAbstractionist's method (I looked at what you did, did it for 2222 whilst looking at yours and then did it for 5555 separately).
I'll have a go using your method now Moo since it seems to be the one in the mark scheme.