1×2+2×3+…+100×101=_.

问题描述:

1×2+2×3+…+100×101=______.

1×2+2×3+3×4+…+100×101
=(12+1)+(22+2)+(32+3)+…+(1002+100)
=(12+22+32+…+1002)+(1+2+3+…+100)
=

100(100+1)(2×100+1)
6
+
100×(100+1)
2

=338350+5050
=343400
故答案为:343400.