So to prove this,
Sub x = -1
And if you solve that equation...
That tells us that if x = + or - 1, the equation will equal to 0...as it does!
With those other two statements...im not quite sure what they are (e.g if they are possible solution from your text book (like multiple choice) or some other wierd expansion...anyhow)
The second statement you definetly cant get from the first...but it equals to zero.
Hope this helped