# easy and quick one

• October 6th 2008, 06:58 AM
ardam
easy and quick one
Erasing x^2 in a cubic equation.
• October 6th 2008, 09:07 AM
Laurent
Try to find $a$ such that, if you replace $x$ by $y-a$ and expand, the coefficient in front of $y^2$ is zero.
• October 6th 2008, 10:34 AM
ThePerfectHacker
Quote:

Originally Posted by ardam
Erasing x^2 in a cubic equation.

If you have $x^3 + ax^2+bx+c = 0$ let $y = x + \frac{a}{3}$.
That should remove the $x^2$ term.
• October 6th 2008, 10:42 AM
ardam
cheers for the help