如题所述
这么写?初二数学,分式运算
通分:
原式=[a^2-(a-2)(a+2)]/(a-2)
=[a^2-a^2+4]/(a-2)
=4/(a-2).
初二数学分式运算
2s÷(s/v1+s/v2)=2÷(1/v1+1/v2)=v1v2/(v1+v2)
初二数学下册分式运算题
1.2/2x-1=4/4x²-1
1/2x-1=2/(2x-1)(2x+1)
1=2/(2x+1)
2x+1=2
x=1/2
2.3/x²+2x - 1/x²-2x=0
3/x(x+2)-1/x(x-2)=0
3(x-2)/x(x²-4)-(x+2)/x(x²-4)=0
(3x-6-x-2)/x(x²-4)=0
2x-8=0
x=4
3.x/x-3=x+1/x-1
x(x-1)=(x+1)(x-3)
x²-x=x²-2x-3
x=-3
4.x-3/x-2 + 1=3/2-x
x-3/x-2 + 1=-3/x-2
x-3+x-2=-3
2x=2
x=1
5.2x+1/x²+x = 5/6x+6
2x+1/x(x+1)=5/6(x+1)
6(2x+1)=5x
12x+6-5x=0
7x=-6
x=-6/7
6.3/2 - 1/3x-1=5/6x-2
[3(3x-1)-2]/2(3x-1)=5/2(3x-1)
9x-3-2=5
9x=10
x=10/9
解:1、原式=(s-2t)2s/(s+2t)=(2s²-4st)/(s+2t)
2、原式=(x-y)/(x+y)× 1/(x-y)²=1/(x²-y²)
3、原式=(u-2u)/(u+2u) - 2/(u+2u)(u-2u)
=(u-2u)²/(u+2u)(u-2u) - 2/(u+2u)(u-2u)
=-(u²-2)/3u²
愿对你有所帮助!
初二数学分式混合运算一题
题目都没有 别人怎么回答
求10道初二数学分式混合运算题
2 a+1-a+3 a2-4a-5÷a2-9 a2-3a-10.
解 原式=[x+2 x(x-2)-x-1(x-2)2]•x 4-x (括号内分式的分母中的多项式式分解因式.分式的除法法则)
=[(x+2)(x-2)x(x-2)2-x(x-1)x(x-2)2]•x4-x(异分母的分式减法的法则)
=x2-4-x2+x x(x-2)2•x4-x (整式运算)
=x-4x(x-2)2•x4-x (合并同类项)
=x-4 x(x-2)2•(-xx-4) (分式的符号法则)
=-1(x-2)2. (分式的乘法法则)
计算x+y x2-xy +(x2-y2 x)2•(1 y-x)3.
解 原式=x+y x(x-y)+(x+y)2(x-y)2x2•1(y-x)3
=x+y x(x-y)-(x+y)2 x2(x-y)
=x2+xy-x2-2xy-y2 x2(x-y)
=-xy-y2 x2(x-y)=-xy+y2 x2(x-y).
x-y+4xy x-y)(x+y-4xyx+y)
答案x2-y2
[1 (a+b)2-1(a-b)2]÷(1a+b-1a-b)
答案2a (a+b)(a-b);
x x-y• y2 x+y-x4y x4-y4÷x2 x2+y2
答案-xy x+y
3x-2 x2-x-2+(1-1x+1)÷(1+1x-1)
答案x2 (x+1)(x-2);
(2x x+1+2 x-1+4x x2-1)×(2x x+1+2 x-1-4x x2-1).
答案4
原创,不许copy
初二数学分式的混合运算求答案
9,化简,
原式
=(2m²-4m-m²-2m)/(m²-4) * (m²-4)/m
=(m²-6m)/(m²-4)* (m²-4)/m
=m-6
10,化简,
(1)原式
=(x-1-x-1)/(x²-1)* (x²-1)/2
=-2/(x²-1)*(x²-1)/2
=-1
(2)原式
=(a²-4+4)/(a²-4)*(a-2)/a
=a²/(a+2)(a-2)*(a-2)/a
=a/(a+2)
(3)原式
=(m+1)/m * (m-1)²/(m+1)(m-1)
=(m-1)/m
11,原式
=(x²-2x+1+2x)/(x²-1) * (x²-1)
=x²+1
无论x=-2还是x=2 ,x²+1都等于5
初二数学 分式 计算
[3x/(x-2)-x/(x+2)] × (x2-4)/x
=[3x(x+2)-x(x-2)/(x-2)(x+2)]×(x2-4)/x
=[3x2+6x-x2-2x/(x-2)(x+2)]×(x2-4)/x
=[x(2x-4)/(x-2)(x+2)]×(x-2)(x+2)/x
=2x-4
OK
初二数学整式运算
用乘法分配律: (15*5^3*3^2-15*5^2+15*5)/15
=5^3*3^2-5^2+5
=1105
你确定题目是这样吗?