# Thread: [SOLVED] Help with powers and roots

1. ## [SOLVED] Help with powers and roots

There's something in my notes that says p^2 is divisible by 3 so p is divisible by 9.
I don't understand this...

If p^2 / 3
shouldn't
p be divisible by 3^(1/2)?

2. Originally Posted by Noxide
There's something in my notes that says p^2 is divisible by 3 so p is divisible by 9. Mr F says: This statement is false. A simple counterexample is p = 6. Speak to your teacher.

I don't understand this...

If p^2 / 3
shouldn't
p be divisible by 3^(1/2)?
A correct statement is if p^2 is divisible by 3 then p is divisible by 3.

3. Is that still true in the context of q^2 = (p^2)/3?
So could I say that p is divisible by 3 and also that q is divisible by 3?

I'm asking this because the weird phrasing of P^2 / 3 so p is divisible by 3 came up in my notes and when i looked it up on the internet it also came up here:

http://mathforum.org/library/drmath/view/52619.html

4. Originally Posted by Noxide
Is that still true in the context of q^2 = (p^2)/3?
So could I say that p is divisible by 3 and also that q is divisible by 3?

I'm asking this because the weird phrasing of P^2 / 3 so p is divisible by 3 came up in my notes and when i looked it up on the internet it also came up here:

Math Forum - Ask Dr. Math
An exact quote of that link is
[snip]
p and q are integers
[snip]

3 q^2 = p^2

So p^2 is divisible by 3. That means that p must be as well, so p^2 is
divisible by nine.
which is very different to what you've said in this thread. I already told you that
if p^2 is divisible by 3 then p is divisible by 3.
.

The proof given in the link is very clear. I don't know exactly what your question or problem is.

5. Haha, now it's a problem.
The problem is that I CANT READ!

Thanks for you help!