初二数学题一道（分式）
\u521d\u4e8c\u6570\u5b66\u4e00\u9053\u5206\u5f0f\u9898\u3002\u53f3\u8fb9\u901a\u5206=[a(x-2)-b(x+2)]/(x+2)(x-2)
=[(a-b)x+(-2a-2b)]/(x²-4)
=4x/(x²-4)
\u6240\u4ee5(a-b)x+(-2a-2b)=4x
\u6240\u4ee5a-b=4
-2a-2b=0
\u5373a-b=4
a+b=0
\u76f8\u52a0
2a=4
a=2
b=-a=-2
\u6240\u4ee5a²+b²=4+4=8
\u5206\u5b50\u5206\u6bcd\u540c\u65f6\u9664\u4ee5X
1/(x-1+1/x)=7
1/7=x-1+1/x
x+1/x=8/7
（1/X（X+2））+（1/（X+2）(X+4)）+（1/(X+4)(X+6))+……+（1/（X+2001）（X+2003）)=1/2(1/X-1/x+2+1/x+2-1/X+4+1/X+4........+1/X+2001-1/X+2003)
=2003/2x平方-4006x
怎么现在初中学这种东西啊
1/11*13 1/(2n-1)*(2n+1)
（1/X（X+2））+（1/（X+2）(X+4)）+（1/(X+4)(X+6))+……+（1/（X+2001）（X+2003）)=1/2(1/X-1/x+2+1/x+2-1/X+4+1/X+4........+1/X+2001-1/X+2003)
=2003/2x平方-4006x
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