Factoriser : x2 + 5x - 10
x2 : x au carré
![Factoriser x2 5x 10 x2 x au carré class=](https://fr-static.z-dn.net/files/d3c/5dd3514d047c2cc547448fa982aacc46.jpg)
2 (x² + 5x - 10) 2x² + 10x - 20
-------------------- = -----------------------
x² x²
= (x - 5)(x +5)
x²