1/1×2×3+1/2×3×4+1/3×4×5+1/4×5×6+...+1/48×49×50的计算过 ...
发布网友
发布时间:2024-10-03 17:28
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热心网友
时间:2024-10-06 18:37
1/1×2×3+1/2×3×4+1/3×4×5+1/4×5×6+.......+1/48×49×50
=(1/2)*(1/1×2-1/2×3)+(1/2)*(1/2×3-1/3×4)+.....(1/2)*(1/48×49-1/49×50)
=(1/2)*(1/1×2-1/2×3+1/2×3-1/3×4+1/3×4.....+1/48×49-1/49×50)
=(1/2)*(1/1×2-1/49×50)
=(1/2)*(1224/2450)
=612/2450
=306/1225
热心网友
时间:2024-10-06 18:35
你好