如题所述
第1个回答 2014-02-22
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追答
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追答
请点击右上角的采纳按钮,谢谢~