Hello, I am stuck with this problem from Gelfand's Algebra book:
Problem 126. Prove that if , then there are two opposite numbers among
To be honest, I don't understand the question.
Hello, DIOGYK!
I think I got it . . .
We have: .
. . . . . . . .
. . . . . . . . . . . .
. . . . . . . . . . . .
. .
n .
. . . . . . .
Factor: . . . . .
. . . . . . . . . . .
. . . . . . . . . .
Factor: . . . . . . . . .
We see that the product of three factors equals zero.
Hence, at least one of the factors must be zero.
Therefore: .