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1.(x-2/x+2)-16/x2-4=x+2/x-2

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1.(x-2/x+2)-16/x2-4=x+2/x-2
2.1- x-3/x-1=x2-2/x2-8x+7 -5-x/7-x
3.当x等于 时,分式1/2x-1无意义;当x= 时,分式 x的绝对值-2/x-2值为零
4.当x= 时,分式3/2x-1与分式3/x-4互为相反数
5.若方程2x/1-2x +3 +k/2x-1=0有增根,则k=
6.(2m/m2-4 -1/m-2)除以(1- 1/m+2)
7.(x/x-2 - x/x+2) 除以4x/x-2
8.(2/3x -2/x+y(x+y/3x -x-y)除以x-y/x
9.(1- 2x/x+y)除以 x2-2xy+y2/3x+3y + x2+xy/x2-y2
10.已知a-2b=2 a不等于1 求 a2-4b2/a2-4b2+a+2b -a2+4ab-4b2的值
11.1/x2-2x -1/x =2/x-2
12.2x-1/x+4 -5= 96/x2-16 -1-3x/4-x
13.1/x2-5x+6 -2/x2-4x+3 + 1/x2-3x+2
感激不尽 越快越好!
1.(x-2/x+2)-16/x2-4=x+2/x-2
1.(x-2/x+2)-16/x2-4=x+2/x-2
(x-2)² - 16 = (x+2)²
x²-4x+4-16 = x²+4x+4
8x = -16
x=-2
2、1- x-3/x-1=x²-2/x²-8x+7 -(5-x/7-x)
1- x-3/x-1=(x²-2)/(x-7)(x-1) +(5-x/x-7)
x²-8x+7 - (x-3)(x-7) = x²-2 - (x-5)(x-1)
x²-8x+7 - x² + 10x -21 = x²-2 -x² + 6x -5
2x - 14 = 6x -7
4x = -7
x = -7/4
3.当x等于(1/2)时,分式1/2x-1无意义;当(x=2或-2)时,分式 x的绝对值-2/x-2值为零
4.当x= 时,分式3/2x-1与分式3/x-4互为相反数
3/2x-1=-(3/x-4)
3x - 12 = -6x +3
9x = 15
x = 5/3
5.若方程2x/1-2x +3 +k/2x-1=0有增根,则k=
2x/1-2x +3 +k/2x-1=0
-2x + 3(2x-1) + k =0
4x = 3-k
x = (3-k)/4
所以 k<3
6.[(2m/m²-4) -1/(m-2)]÷ [1- 1/(m+2)]
=[(2m-m+2)/(m²-4)]÷[(m+2-1)/(m+2)]
=[(m+2)/(m²-4)]×[(m+2)/(m+1)
= 1/(m+1)
7.(x/x-2 - x/x+2) ÷ 4x/x-2
=[(x²+2x)/(x²-4) - (x²-2x)/(x²-4)] × (x-2)/(4x)
=[ (4x)/(x²-4)]×(x-2)/4x
= 1/(x+2)
8.(这题看不清
9.(1- 2x/x+y)÷( x²-2xy+y²)/(3x+3y) + x²+xy/x²-y²
= (x+y-2x)/(x+y) × (3x+3y)/(x-y)² + x/(x-y)
= -(x-y)/(x+y) × (3x+3y)/(x-y)² + x/(x-y)
= -3/(x-y) + x/(x-y)
= (x-3)/(x-y)
10.已知a-2b=2 ,a不等于1 ,求 (a²-4b²)/(a²-4b²+a+2b -a²+4ab-4b²的值
这题也看不懂题目,自己先用后面的式子化简,化简后会得到(a-2b)的形式的
11.1/x²-2x -1/x =2/x-2
1/x(x-2) - 1/x = 2/(x-2)
两边同时乘以x(x-2)
1 - (x-2) = 2x
-x +3 =2x
x = 1
12.(2x-1/x+4) -5= (96/x²-16) -(1-3x/4-x)
两边同时乘以x²-16 ,相当于乘以(x+4)(x-4)
(2x-1)(x-4) -5(x²-16) =96 - (3x-1)(x+4)
2x² - 9x + 4 - 5x² + 80 =96 - 3x² - 12x +x +4
-3x² - 9x + 84 = 100 -3x² -11x
2x = 16
x = 8
13.1/x²-5x+6 -2/x²-4x+3 + 1/x²-3x+2
= 1/(x-2)(x-3) - 2/(x-1)(x-3) + 1/(x-1)(x-2)
分母上下同时乘以(x-1)(x-2)(x-3)
= (x-1) - 2(x-2) + (x-3)
= x-1 -2x +4 + x-3
= 0
以后写题目时清楚点,好几个都看不太清楚