hello?

Hi

:0

Sorry i dont really understand why d|r

So your approach is basically sound.... You're trying to show gcd(a,b) = gcd(b,r) by showing the divide one another correct?

Yeah

Okay, so suppose that x divides y and x divides z

Ok

Do you see why z divides my + nz no matter what m,n are?

err.. why x divides?

yes

cause it divides both parts

u can write z as a c1x and y as c2x

exactly good

So, we have a = bq + r which means r = a -bq

and d= gcd(a,b) divides a and b right?

lol

then a=c1d and b = c2d

thus d divides r

yup!

Ah that makes sence :)

i was worried about that for sure!

Thank you so much for that :)

yeah no prob

Obvious proofs are always the hardest to prove

for me at least, hard to find that unique something makes them tick :)

yeah it takes some practise...