How do I factor this polynomial: $2x^2-5xy-y^2$ ?
How to factor the quadratic polynomial $2x^2-5xy-y^2$?
3
$\begingroup$
algebra-precalculus
polynomials
quadratics
factoring
quadratic-forms
-
0Do you know how to factor $2x^2 - 5x - 1$? – 2012-05-25
-
0It doesn't have an iteger factorization. The only candidates are (2x+y)(x-y) and (2x-y)(x+y) but the first expands to 2x^2-xy-y^2 and the second to 2x^2+xy-y^2. – 2012-05-25
-
0@TonyK i tried, but it didnt work.. :( – 2012-05-25
-
2Are you sure there is no typo? Perhaps one of the following was intended. $$ 2x^2 -xy-y^2\ =\ (x-y)(2x+y)$$ $$ 2x^2 -5xy-3y^2\ =\ (x-3y)(2x+y)$$ $$ 2x^2 -5xy+2y^2\ =\ (x-2y)(2x-y)$$ $$ 2x^2 -5xy+3y^2\ =\ (x-y)(2x-3y)$$ – 2012-05-25
-
0Two possible factorizations are $$\begin{eqnarray*} 2x^{2}-5xy-y^{2} &=&2\left( x-\frac{5+\sqrt{33}}{4}y\right) \left( x-\frac{5- \sqrt{33}}{4}y\right) \\ &=&-\left( y+\frac{5-\sqrt{33}}{2}x\right) \left( y+\frac{5+\sqrt{33}}{2} x\right) \end{eqnarray*}$$ – 2012-08-31