(x+1)(x+2)=2x+4 一元二次方程 (x+1)方=4x 2x方-10x=3 (x-2)(x-5)=-2
问题描述:
(x+1)(x+2)=2x+4 一元二次方程 (x+1)方=4x 2x方-10x=3 (x-2)(x-5)=-2
答
(x+1)(x+2)=2x+4x^2+x-2=0(x-1)(x+2)=0x1=1,x2=-2(x+1)方=4xx^2-2x+1=0(x-1)^2=0x=12x方-10x=3x^2-5x=3/2(x-(5/2))^2=(3/2)+(25/4)x-(5/2)=+ -(1/2)(根号31)x1=(5/2)+(1/2)(根号31),x2=(5/2)-(1/2)(根号31)(x-2)(...