2×1/1+2×3/1+3×4/1+4×5/1+……49×50/1怎么解?

来源：学生作业学帮网编辑：学帮网时间：2024/06/05 02:32:13

2×1/1+2×3/1+3×4/1+4×5/1+……49×50/1
=(1/1-2/1)+(2/1-3/1)+……+(49/1-50/1)
=1-50/1
=50/49

2×1/1+2×3/1+3×4/1+4×5/1+……49×50/1
=1-2/1+2/1-3/1+3/1-4/1+-------+49/1-50/1
=1-50/1
=50/49

2×1/1+2×3/1+3×4/1+4×5/1+......49×50/1
=(1/1-2/1)+(2/1-3/1)+......+(49/1-50/1)
=1-50/1
=50/49

50/49

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