①x²-3x+1=0②（x-1）²=3③x²-3x=0④x²-2x=4

①x²-3x+1=0②（x-1）²=3③x²-3x=0④x²-2x=4
①x²-3x+1=0
②（x-1）²=3
③x²-3x=0
④x²-2x=4

①x²-3x+1=0②（x-1）²=3③x²-3x=0④x²-2x=4
①x²-3x+1=0
x²-3x+9/4=5/4
(x-3/2)²=5/4
x=3/2+√5/2 x=3/2-√5/2
②（x-1）²=3
x=1+√3 x=1-√3
③x²-3x=0
x(x-3)=0
∴x=0 x=3
④x²-2x=4
x²-2x+1=5
(x-1)²=5
x=1+√5 x=1-√5

1) 配方
x²-3x+1=0


x²-3x+9/4=5/4

(x-3/2)² = 5/4

x-3/2 = ±√5/2

x = ±√5/2 +3/2

2) (x-1)²=3


x-1 = ±√3
...

全部展开

1) 配方
x²-3x+1=0


x²-3x+9/4=5/4

(x-3/2)² = 5/4

x-3/2 = ±√5/2

x = ±√5/2 +3/2

2) (x-1)²=3


x-1 = ±√3

x = ±√3+1

3)还是配方
x²-3x=0
x²-3x +9/4=9/4
(x-3/2)² = 9/4
x-3/2 = ±3/2
x = 0 或3

4）配方
x²-2x=4

x²-2x +1=5

(x-1)² = 5
x-1 = ±√5
x = ±√5+1

收起

1.9-4=5
x=(3+-5^1/2)/2
2.（x-1)^2=3
x-1=+-3^1/2
x=1+-3^1/2
3.x^2-3x=0
x(x-3)=0
x1=0,x2=3
4.x^2-2x-4=0
4+16=20
x=(2+-2*5^1/2)/2=1+-5^1/2

1. X（x-3）=-1 2.x²+x-1=3 3.x²=3x 4.x(x-2)=4
x=-1/x-3 x(x+1)=4 x=3或者0 x=4/x-2
x=4/x+1