Square of Sum less Square/Algebraic Proof 2
Jump to navigation
Jump to search
Theorem
- $\forall x, y \in \R: \paren {2x + y} y = \paren {x + y}^2 - x^2$
Proof
\(\ds \paren {x + y}^2 - x^2\) | \(=\) | \(\ds \paren {x + y + x} \paren {x + y - x}\) | Difference of Two Squares | |||||||||||
\(\ds \) | \(=\) | \(\ds \paren {2 x + y} y\) |
$\blacksquare$