(1)计算:11×3+13×5+…+12011×2013;(2)若|x-1|+|y+1|=0,试求:1x(y+3)+1(x+1)(y+4)+1(x+2)(y+5)+…+1(x+2011)(y+2014)的值;(3)若n为整数,且(11×4+14×7+17×10+…+12002×2005)×-数学

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1(x+2)(y+5)+…+
1
(x+2011)(y+2014)

=1-
1
2
+
1
2
-
1
3
+
1
3
-
1
4
+…+
1
2012
-
1
2013

=1-
1
2013

=
2012
2013


(3)
1
1×4
+
1
4×7
+
1
7×10
+…+
1
2002×2005

=
1
3
×(1-
1
4
+
1
4
-
1
7
+…+
1
2002
-
1
2005

=
1
3
×(1-
1
2005

=
1
3
×
2004
2005

=
668
2005

∵(
1
1×4
+
1
4×7
+
1
7×10
+…+
1
2002×2005
)×|n|<1,
∴n=-3或-2或-1或0或1或2或3,
∴当n=-3时,n2+n=6;
当n=-2时,n2+n=2;
当n=-1时,n2+n=0;
当n=0时,n2+n=0;
当n=1时,n2+n=2;
当n=2时,n2+n=6;
当n=3时,n2+n=12.

据专家权威分析,试题“(1)计算:11×3+13×5+…+12011×2013;(2)若|x-1|+|y+1|=0,试求:1x(..”主要考查你对  绝对值,代数式的求值   等考点的理解。关于这些考点的“档案”如下: