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如果有理数x,y满足|x-1|+(xy-2)2=0.(1)求x,y的值;(2)试求1xy+1(x+1)(y+1)+1(x+2)(y+2)+…+1(x+2009)(y+2009)的值.

题目详情
2

1
xy
+
1
(x+1)(y+1)
+
1
(x+2)(y+2)
+…+
1
(x+2009)(y+2009)
的值.
1
xy
11xyxy
1
(x+1)(y+1)
11(x+1)(y+1)(x+1)(y+1)
1
(x+2)(y+2)
11(x+2)(y+2)(x+2)(y+2)
1
(x+2009)(y+2009)
11(x+2009)(y+2009)(x+2009)(y+2009)
▼优质解答
答案和解析
(1)∵x-1|≥0,(xy-2)22≥0,又|x-1|+(xy-2)22=0
∴|x-1|=0;(xy-2)22=0
∴x=1,y=2;
(2)原式=
1
2
+
1
2×3
+
1
3×4
+
1
4×5
+…+
1
2010×2011

=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2
111222+
1
2×3
+
1
3×4
+
1
4×5
+…+
1
2010×2011

=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2×3
1112×32×32×3+
1
3×4
+
1
4×5
+…+
1
2010×2011

=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
3×4
1113×43×43×4+
1
4×5
+…+
1
2010×2011

=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
4×5
1114×54×54×5+…+
1
2010×2011

=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2010×2011
1112010×20112010×20112010×2011
=
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2
111222+
1
2
-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2
111222-
1
3
+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
3
111333+
1
3
-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
3
111333-
1
4
+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
4
111444+
1
4
-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
4
111444-
1
5
+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
5
111555+…+
1
2009
-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2009
111200920092009-
1
2010
+
1
2010
-
1
2011
=
2010
2011
1
2010
111201020102010+
1
2010
-
1
2011
=
2010
2011
1
2010
111201020102010-
1
2011
=
2010
2011
1
2011
111201120112011=
2010
2011
2010
2011
201020102010201120112011.