计算100²-99²+98²-97²+96²-95²+…+2²-1²
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计算100²-99²+98²-97²+96²-95²+…+2²-1²
计算100²-99²+98²-97²+96²-95²+…+2²-1²
计算100²-99²+98²-97²+96²-95²+…+2²-1²
100²-99²+98²-97²+96²-95²+…+2²-1²
=(100+99)×(100-99)+(98+97)×(98-97)+(96+95)×(96-95)+……+(2+1)×(2-1)
=100+99+98+97+96+95+……+2+1
=(100+1)+(99+2)+(98+3)+……+(52+49)+(51+50)
=101×50
=5050
100²-99²+98²-97²+96²-95²+…+2²-1²
=(100+99) + (98+97) + ... + (2+1)
=(100 * 101)/2
=5050
你,有病吧
=(100+99)*(100-99)+(98+97)(98-97)+......+(2+1)(2-1)
=100+99+98+.......+2+1
=5050