>
数学
>
计算:
(
1
2
+
1
3
+…+
1
2002
)(1+
1
2
+
1
3
+…+
1
2001
)−(1+
1
2
+…+
1
2002
)(
1
2
+
1
3
+…+
1
2001
)
人气:164 ℃ 时间:2020-04-13 19:35:28
解答
假设:a=1+
1
2
+
1
3
+…
1
2001
,b=
1
2
+
1
3
+…+
1
2001
,
即a-b=1,
∴原式=(b+
1
2002
)a-(a+
1
2002
)b,
=ab+a×
1
2002
-ab-b×
1
2002
,
=(a-b)×
1
2002
又∵a-b=1
∴原式=
1
2002
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