内容正文:
第二十一章一元二次方程解方程50题专项训练
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(4)x2+4r-1■0
1)4x-1y3=9
(5)(2x-5j=2x-5
(2)3到-2-242-x
(6)(4r-3)2=25
(3)2x(x-3)=x-1川x+
(7)3x(x-7)=2(7-x)
(8)x2+2.xw0
(12》x-6x-1-0(配方法)
(9)x2-5x+4=0
(13)2x+x-1=0(公式法)
(10)r-2x-3=0
(14>x2-2x-1=0
(11)5x2-4x-1,0
(15)(x-2°+2(x-2=0
2
(16)x2-6x+5=0
20)32r+)=4r+2
(17)x-4x-5=0
(21)-2=3y-2
(18)(2--32x-
(22)x2+8x-9=0
(19)(+8-5到x+8+6=0
(23)x2-4=0
0=1-x2-:x(1E)
0=7+x+,x(L2)
1+zb=,b-x)0E)
0=9+7-L(9元)
牛
0=1--h(S元)
0=6-x9+:L-<87》
£+rg=fL+xr(忆)
(32)3xx-1-2r-2
(36)2+2x-3=0(配方法)
(33)x2-6x-15=0
(37)5r+2=3r(公式法)
(34)3r2-2x-6=0
(38)(-2少'-(2x-3》(因式分解法)
(35)(3x+2少=25(直接开平方法)
(39)2x2=4x
(40)2x2-3x+1=0
《45》x-2x-4=0:(尼方法)
(41)-7)=87-
(46)4r-)=-1(适当方法)
(42)x2-81=0
(47)92+12=16
(43)3-3到=2-3到(因式分解法)
(48)x2-4x+5=0
(44)x2-4r+5=0:(公式法)
6
0=S-t+:x7(0S)
p=1+z-x(6价)
参考答案
2)4=26青
(3)x=3+22,x1=3-22
(4)x=-2+5,2=-2-5
5务
(6)y=-
2’5-2
(7)x=7,3=-3
2
(8)x=0,x2=-2
(9)x=1,x2=4
(10)x=3,x2=-1
0)=,6=月
(12)x=10+3,x=-0+3
13)x=小-5
4
4
(14)x=1+2,1=1-V2
(15)x1=2,x2=0
(16)x=1,x2=5
(17)x1=-1,x2=5
18》6=2或5=2
(19)x1=-6,x2=-5
m=片月
(21)y1=2,2=3
(22)x1=1,x3=-9
(23)x=-2,5=2
(24)x=3,x2=-1
(25)5=1+
1-2
2水
2
(26)x=3,=7
(27)方程无实数解
(28)方程无实数解
(29)分式方程无解
30)x=。或=-2
(31):=1+2,x=1-2
2)1,6号
(33)=3+26,x,=3-26
(34)=1+@
3
3
(35)x=1,=
7
(36)x=1,x1=-3
(37)x=2,=-3
1
5
(38)¥=3×=1
(39),=0,5=2
(40)x=1,5=2
(41)x=-8,x2=7
(42)x=9x2=-9
2
(43)=3,名=
(44)原方程无实数根
(45)x1=1-5,x,=1-5
(460=6月
(47)x=a+b,x2=a-b
(48)无解
(49)x1=3,x2=-1
(50)x=-2+14
2
524
2