初三难度的一些解方程题目3x²=271/2(y-2)²=84(2x-1)²-9=0x²-4x+4=7x²+10x+9=03x²-6x-9=02x²-5x+2=02x²--6x-82x²+4x=0x²-2/3x+2/3=00.4x²-0.8x-1=0y²+1=2乘3的平方根再乘yx
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初三难度的一些解方程题目3x²=271/2(y-2)²=84(2x-1)²-9=0x²-4x+4=7x²+10x+9=03x²-6x-9=02x²-5x+2=02x²--6x-82x²+4x=0x²-2/3x+2/3=00.4x²-0.8x-1=0y²+1=2乘3的平方根再乘yx
初三难度的一些解方程题目
3x²=27
1/2(y-2)²=8
4(2x-1)²-9=0
x²-4x+4=7
x²+10x+9=0
3x²-6x-9=0
2x²-5x+2=0
2x²--6x-8
2x²+4x=0
x²-2/3x+2/3=0
0.4x²-0.8x-1=0
y²+1=2乘3的平方根再乘y
x²-2x-1=0
2x²-7x+6=0
2(x²-3x)=5-6x
x²-2x=8
(2x-1)(x-2)=5
3x²-2乘3的平方根再乘x=1
5x²+2x-1=0
6y²-13y+6=0
x²-2x+8=0
x²=2乘3的平方根再乘X在减3
3m²-4m-4=0
(3x-4)²=(4x-3)²
2x²-6x=5x-15
(2x-1)(x+1)=(3x+1)(x+1)
3x²-12/x+2=2x
初三难度的一些解方程题目3x²=271/2(y-2)²=84(2x-1)²-9=0x²-4x+4=7x²+10x+9=03x²-6x-9=02x²-5x+2=02x²--6x-82x²+4x=0x²-2/3x+2/3=00.4x²-0.8x-1=0y²+1=2乘3的平方根再乘yx
3x²=27
x²=9
x=3或x=-3
1/2(y-2)²=8
(y-2)²=16
y-2=4或y-2=-4
y=6或y=-2
4(2x-1)²-9=0
(2x-1)²=9/4
2x-1=3/2或2x-1=-3/2
2x=5/2或2x=-1/2
x=5/4或x=-1/4
x²-4x+4=7
(x-2)²=7
x-2=√7或x-2=-√7
x=2+√7或x=2-√7
x²+10x+9=0
x²+10x+25=16
(x+5)²=16
x+5=4或x+5=-4
x=-1或x=-9
3x²-6x-9=0
x²-2x-3=0
x²-2x+1=4
(x-1)²=4
x-1=2或x-1=-2
x=3或x=-1
2x²-5x+2=0
(2x-1)(x-2)=0
2x-1=0或x-2=0
x=1/2或x=2
2x²--6x-8=0
x²-3x-4=0
(x+1)(x-4)=0
x+1=0或x-4=0
x=-1或x=4
2x²+4x=0
x²+2x=0
x(x+2)=0
x=0或x=-2
x²-2/3x+2/3=0
△=(2/3)²-4*2/3=9/4-8/3<0
方程无实数根
0.4x²-0.8x-1=0
2x²-4x-5=0
△=4²+4*2*5=56
x=(4±√56)/4=(2±√13)/2
y²+1=2乘3的平方根再乘y
y²+1=2√3*y
y²-2√3*y+1=0
y²-2√3*y+3=2
(y-√3)²=2
y-√3=√2或y-√3=-√2
y=√3+√2或y=√3-√2
x²-2x-1=0
x²-2x+1=2
(x-1)²=2
x-1=±√2
x=1±√2
2x²-7x+6=0
(x-2)(2x-3)=0
x-2=0或2x-3=0
x=2或x=3/2
2(x²-3x)=5-6x
2x²-6x=5-6x
x²=5/2
x=±√(5/2)
x=±√10/2
x²-2x=8
x²-2x-8=0
(x+2)(x-4)=0
x=-2或x=4
(2x-1)(x-2)=5
2x²-5x-3=0
(2x+1)(x-3)=0
2x+1=0或x-3=0
x=-1/2或x=3
3x²-2乘3的平方根再乘x=1
3x²-2√3x=1
x²-2*√3/3x=1/3
x²-2*√3/3x+1/3=2/3
(x-√3/3)²=2/3
x-√3/3=±√6/3
x=(√3±√6)/3
5x²+2x-1=0
△=4+4*5*1=24
x=(-2±√24)/10
x=(-1±√6)/5
6y²-13y+6=0
△=13²-6×6×6=-47<0
方程无实数根
x²-2x+8=0
△=4-32=-28<0
方程无实数根
x²=2乘3的平方根再乘X在减3
x²=2√3*x-3
x²-2√3x+3=0
(x-√3)²=0
x=√3
3m²-4m-4=0
(m-2)(3m+2)=0
m-2=0或3m+2=0
m=2或m=-2/3
(3x-4)²=(4x-3)²
3x-4=4x-3或3x-4=3-4x
x=-1或x=1
2x²-6x=5x-15
2x²-11x+15=0
(x-3)(2x-5)=0
x-3=0或2x-5=0
x=3或x=5/2
(2x-1)(x+1)=(3x+1)(x+1)
(x+1)(3x+1-2x+1)=0
(x+1)(x+2)=0
x+1=0或x+2=0
x=-1或x=-2
3x²-12/x+2=2x
这题看不明白
写清楚点再追问吧
3x²=27 X=+-3
1/2(y-2)²=8 y=6或y=-2
4(2x-1)²-9=0 x=-1或x=5
x²-4x+4=7 x=3
x²+10x+9=0 x=-9,x=-1
3x²-6x-9=0 x=3,x=-1
2x²...
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3x²=27 X=+-3
1/2(y-2)²=8 y=6或y=-2
4(2x-1)²-9=0 x=-1或x=5
x²-4x+4=7 x=3
x²+10x+9=0 x=-9,x=-1
3x²-6x-9=0 x=3,x=-1
2x²-5x+2=0 x=0.5,x=2
2x²--6x-8 ?
2x²+4x=0 x=0,x=-2
x²-2/3x+2/3=0
0.4x²-0.8x-1=0
y²+1=2乘3的平方根再乘y
x²-2x-1=0
2x²-7x+6=0
2(x²-3x)=5-6x
x²-2x=8
(2x-1)(x-2)=5
3x²-2乘3的平方根再乘x=1
5x²+2x-1=0
6y²-13y+6=0
x²-2x+8=0
x²=2乘3的平方根再乘X在减3
3m²-4m-4=0
(3x-4)²=(4x-3)²
2x²-6x=5x-15
(2x-1)(x+1)=(3x+1)(x+1)
3x²-12/x+2=2x
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(1)3x²=27
x²=9
x=±3
(2)1/2(y-2)²=8
(y-2)²=16
y-2=±4
y=6 y=-2
(3)4(2x-1)²-9=0
(2x-1)²=9/4
2x-1=±3/2
x=5/4 x=-1/4
(4)x²-4...
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(1)3x²=27
x²=9
x=±3
(2)1/2(y-2)²=8
(y-2)²=16
y-2=±4
y=6 y=-2
(3)4(2x-1)²-9=0
(2x-1)²=9/4
2x-1=±3/2
x=5/4 x=-1/4
(4)x²-4x+4=7
x²-4x-3=0
b²-4ac=28
x=2±√7
(5)x²+10x+9=0
(x+1)(x+9)=0
x=-1 x=-9
(6)3x²-6x-9=0
x²-2x-3=0
(x-3)(x+1)=0
x=3 x=-1
(7)2x²-5x+2=0
1 -2
2 -1
(x-2)(2x-1)=0
x=2 x=1/2
(8)2x²--6x-8=0
x²--3x-4=0
(x-4)(x+1)=0
x=4 x=-1
(9)2x²+4x=0
2x(x+2)=0
x=0 x=-2
(10)x²-2/3x+2/3=0
b²-4ac=4/9-4(2/3)<0
无解
(11)0.4x²-0.8x-1=0
2x²-4x-5=0
b²-4ac=16-4*2*(-5)=56
x=(2±√14)/2
(12)y²+1=2√3y
y²-2√3y+1=0
b²-4ac=8
y=√3±√2
(13)x²-2x-1=0
b²-4ac=4-4(-1)=8
x=1±√2
(14)2x²-7x+6=0
1 -2
2 -3
(x-2)(2x-3)=0
x=2 x=3/2
(15)2(x²-3x)=5-6x
2x²-6x+6x=5
2x²=5
x²=5/2
x=±√5/√2
(16)x²-2x-8=0
1 -4
1 2
(x-4)(x+2)=0
x=4 x=-2
(17)(2x-1)(x-2)=5
2x²-4x-x+2-5=0
2x²-5x-3=0
1 -3
2 1
(x-3)(2x+1)=0
x=3 x=-1/2
(18)3x²-2√3x-1=0
b²-4ac=12-4*3*(-1)=24
x=(√3±√6)/3
(19)5x²+2x-1=0
b²-4ac=24
x=(-1±√6)/5
(20)6y²-13y+6=0
2 -3
3 -2
(2y-3)(3y-2)=0
y=3/2 y=2/3
x²-2x+8=0
(21)x²-2√3X+3=0
(x-√3)²=0
x=√3
(22)3m²-4m-4=0
1 -2
3 2
(m-2)(3m+2)=0
m=2 m=-2/3
(23)(3x-4)²=(4x-3)²
3x-4=±4x-3
x=-1 x=1
(24)2x²-6x=5x-15
2x²-11x+15=0
1 -3
2 -5
(x-3)(2x-5)=0
x=3 x=5/2
(25)(2x-1)(x+1)=(3x+1)(x+1)
2x-1=3x+1
x=-2
(26)3x²-12/x+2=2x
没看懂,用文字说明一下
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3x²=27
x²=9
x=±3
1/2(y-2)²=8
(y-2)²=16
y-2=±4
y=6或-2
4(2x-1)²-9=0
[2(2x-1)-3][2(2x-1)+3]=0
[4x-2...
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3x²=27
x²=9
x=±3
1/2(y-2)²=8
(y-2)²=16
y-2=±4
y=6或-2
4(2x-1)²-9=0
[2(2x-1)-3][2(2x-1)+3]=0
[4x-2-3][4x-2+3]=0
(4x-5)(4x+1)=0
4x=5或-1
x=5/4或-1/4
x²-4x+4=7
(x-2)²=7
x-2=±根号7
x=±根号7+2
x²+10x+9=0
(x+1)(x+9)=0
x=-1或-9
3x²-6x-9=0
x=-6±根号[(-6)²-4*3*(-9)]/3*2
x=-6±根号(36+108)/6
x=-6±12/6
x=1或-3
2x²-5x+2=0
x=-5±根号[(-5)²-4*2*2]/2a
x=-5±根号(25-16)/2*2
x=-5±3/4
x=-1/2或-2
2x²--6x-8=0
2(x²-3x-4)=0
x²-3x-4=0
(x-4)(x+1)=0
x=4或-1
2x²+4x=0
2x(x+4)=0
x+4=0
x=-4
x²-2/3x+2/3=0
3x²-2x+2=0
∵b²-4ac<0
所以该方程无解
0.4x²-0.8x-1=0
2x²-4x-5=0
x=(4±√4²+4*2*5)/4
x=(2±√13)/2
y²+1=2乘3的平方根再乘y
y²+1=2√3*y
y²-2√3*y+1=0
y²-2√3*y+3=2
(y-√3)²=2
y-√3=√2或y-√3=-√2
y=√3+√2或y=√3-√2
x²-2x-1=0
x²-2x+1=2
(x-1)²=2
x-1=±√2
x=1±√2
2x²-7x+6=0
(x-2)(2x-3)=0
x-2=0或2x-3=0
x=2或x=3/2
2(x²-3x)=5-6x
2x²-6x=5-6x
x²=5/2
x=±√(5/2)
x=±√10/2
x²-2x=8
x²-2x-8=0
(x+2)(x-4)=0
x=-2或x=4
(2x-1)(x-2)=5
2x²-5x-3=0
(2x+1)(x-3)=0
2x+1=0或x-3=0
x=-1/2或x=3
3x²-2乘3的平方根再乘x=1
3x²-2√3x=1
x²-2*√3/3x=1/3
x²-2*√3/3x+1/3=2/3
(x-√3/3)²=2/3
x-√3/3=±√6/3
x=(√3±√6)/3
5x²+2x-1=0
x=(-2±√4+4*5*1)/10
x=(-1±√6)/5
6y²-13y+6=0
∵b²-2ac=13²-6×6×6=-47<0
∴方程无实数根
x²-2x+8=0
∵b²-2ac=4-32=-28<0
∴方程无实数根
x²=2乘3的平方根再乘X在减3
x²=2√3*x-3
x²-2√3x+3=0
(x-√3)²=0
x=√3
3m²-4m-4=0
(m-2)(3m+2)=0
m-2=0或3m+2=0
m=2或m=-2/3
(3x-4)²=(4x-3)²
3x-4=4x-3或3x-4=3-4x
x=-1或x=1
2x²-6x=5x-15
2x²-11x+15=0
(x-3)(2x-5)=0
x-3=0或2x-5=0
x=3或x=5/2
(2x-1)(x+1)=(3x+1)(x+1)
(x+1)(3x+1-2x+1)=0
(x+1)(x+2)=0
x+1=0或x+2=0
x=-1或x=-2
(3x²-12)/x+2=2x
3x-12/x+2=2x
3x²-12+2x=2x²
x²+2x-12=0
∵b²-2ac<0
∴方程无实数根
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