用配方法解方程(1)2x²-5x+3=0(2)4x²-3x+1(3)2/3y²+1/3y-2=0(4)0.4x²-0.8x=1
问题描述:
用配方法解方程(1)2x²-5x+3=0(2)4x²-3x+1(3)2/3y²+1/3y-2=0(4)0.4x²-0.8x=1
答
(1) (2x-3)*(x-1)=0
x=3/2或x=1
(2) (4x+1)*(x-1)
(3) (2/3y-1)*(y+2)=0
y=3/2或y=-2
(4) 解不出配方法不是十字相乘(1)2(x-5/4)^2-1/8=0
(2)(2x-3/4)^2+7/16
(3)2(y+1/2)^2-13/2=0
(4)0.4(x-1)^2-1.4=0