两道用配方法解方程的题,急······(1) 0.4x^2-0.5x=1 (2) (2x-1)(x+2)=1

来源:学生作业帮助网 编辑:作业帮 时间:2024/12/02 06:33:15
两道用配方法解方程的题,急······(1) 0.4x^2-0.5x=1 (2) (2x-1)(x+2)=1
x){cϧxlgXxf

两道用配方法解方程的题,急······(1) 0.4x^2-0.5x=1 (2) (2x-1)(x+2)=1
两道用配方法解方程的题,急······
(1) 0.4x^2-0.5x=1
(2) (2x-1)(x+2)=1

两道用配方法解方程的题,急······(1) 0.4x^2-0.5x=1 (2) (2x-1)(x+2)=1
(1) 0.4x^2-0.5x=1
4x²-5x=10
x²-5x/4=5/2
x²-5x/4+25/64=5/2+25/64
(x-5/8)²=185/64
x=5/8+√185/8 x=5/8-√185/8
(2) (2x-1)(x+2)=1
2x²+3x=3
x²+3x/2+9/16=3/2+9/16
(x+3/4)²=33/16
x=-3/4+√33/4 x=-3/4-√33/4