(3X-Y)^2-(2X+Y)^2-(Y+3X)(3X-Y) 因式分解

问题描述:

(3X-Y)^2-(2X+Y)^2-(Y+3X)(3X-Y) 因式分解

原式=9x^2+y^2-6xy-(4x^2+y^2+4xy)-(9x^2-y^2)
=-4x^2-10xy+y^2