Hi guys, need help with two probs below
1. Prove either true or false:
3|(a^2+b^2) => 3|a and 3|b
2. Prove that prime number 7t+1 can also be written as 14s+1
Much appreciated!
Hello, lolcat!
1. Prove either true or false:
. .
This is not a rigorous proof . . .
Note the squares:
.
If is divisible by 3, then: .
We see that the only way that
. . is when both and are divisible by 3.
2. Prove that prime number can also be written as
If is odd,
. . then: .
is not a prime.
Hence, must be even,
Then: .