(1)2(n-1)²+n=1 (2)(2x+1)²-x²=0 (3) x²-6x-19=0(4) 5x(x-3)-(x-3)(x+1)=0 (5)4(3x+1)²=25(x-2)²(6) (x+1)²=2(x+1) (7) 3x(x-1)=2x-2 (8)2(x-3)²=x²-9(9)(x-3)²+4x(x-3)=0 一定要具体啊,

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(1)2(n-1)²+n=1(2)(2x+1)²-x²=0(3)x²-6x-19=0(4)5x(x-3)-(x-3)(x+1)=0(5)4(3x+1)²

(1)2(n-1)²+n=1 (2)(2x+1)²-x²=0 (3) x²-6x-19=0(4) 5x(x-3)-(x-3)(x+1)=0 (5)4(3x+1)²=25(x-2)²(6) (x+1)²=2(x+1) (7) 3x(x-1)=2x-2 (8)2(x-3)²=x²-9(9)(x-3)²+4x(x-3)=0 一定要具体啊,
(1)2(n-1)²+n=1 (2)(2x+1)²-x²=0 (3) x²-6x-19=0
(4) 5x(x-3)-(x-3)(x+1)=0 (5)4(3x+1)²=25(x-2)²
(6) (x+1)²=2(x+1) (7) 3x(x-1)=2x-2 (8)2(x-3)²=x²-9
(9)(x-3)²+4x(x-3)=0
一定要具体啊,

(1)2(n-1)²+n=1 (2)(2x+1)²-x²=0 (3) x²-6x-19=0(4) 5x(x-3)-(x-3)(x+1)=0 (5)4(3x+1)²=25(x-2)²(6) (x+1)²=2(x+1) (7) 3x(x-1)=2x-2 (8)2(x-3)²=x²-9(9)(x-3)²+4x(x-3)=0 一定要具体啊,

(1):2(n-1)²+n=1
2(n-1)²+(n-1)=0
(n-1)[2(n-1)+1]=0
(n-1)(2n-1)=0
n-1=0或2n-1=0
n1=1,n2=1/2
(2):(2x+1)²-x²=0
[(2x+1)+x][(2x+1)-x]=0
(3x+1)(x+1)=0
3x+1=0或x+1=0
x1=-1/3,x2=-1
(3):x²-6x-19=0
x²-6x=19
x²-6x+9=19+9
(x-8)²=28
x-8=±√28
x-8=±2√7
x-8=2√7或x-8=-2√7
x1=8+2√7,x2=8-2√7
(4):5x(x-3)-(x-3)(x+1)=0
(x-3)[5x-(x+1)]=0
(x-3)(4x-1)=0
x-3=0或4x-1=0
x1=3,x2=1/4
(5):4(3x+1)²=25(x-2)²
4(3x+1)²-25(x-2)²=0
[2(3x+1)]²-[5(x-2)]²=0
[2(3x+1)+5(x-2)][2(3x+1)-5(x-2)]=0
(6x+2+5x-10)(6x+2-5x+10)=0
(11x-8)(x+12)=0
11x-8=0或x+12=0
x1=8/11,x2=-12
(6):(x+1)²=2(x+1)
(x+1)²-2(x+1)=0
(x+1)[(x+1)-2]=0
(x+1)(x-1)=0
x+1=0或x-1=0
x1=-1,x2=1
(7):3x(x-1)=2x-2
3x(x-1)-(2x-2)=0
3x(x-1)-2(x-1)=0
(x-1)(3x-2)=0
x-1=0或3x-2=0
x1=1,x2=2/3
(8):2(x-3)²=x²-9
2(x-3)²-(x²-9)=0
2(x-3)²-(x+3)(x-3)=0
(x-3)[2(x-3)-(x+3)]=0
(x-3)(2x-6-x-3)=0
(x-3)(x-9)=0
x-3=0或x-9=0
x1=3,x2=9
(9):(x-3)²+4x(x-3)=0
(x-3)[(x-3)+4x]=0
(x-3)(5x-3)=0
x-3=0或5x-3=0
x1=3,x2=3/5