[Toán 8] Phân tích đa thức thành nhân tử.

H

harrypham

$$\begin{aligned} 4x^2-6x-19 & =(2x)^2-2.2x. \dfrac{3}{2}+ \left( \dfrac{3}{2} \right)^2 - \dfrac{85}{4} \\ & = \left( 2x- \dfrac{3}{2} \right)^2 - \left( \dfrac{\sqrt{85}}{2} \right)^2 \\ & = \left( 2x- \dfrac{3}{2} - \dfrac{\sqrt{85}}{2} \right) \left( 2x- \dfrac{3}{2}+ \dfrac{\sqrt{85}}{2} \right) \end{aligned}$$
 
You must log in or register to reply here.
Top Bottom