Question

Chứng minh (1-1/3)(1-1/6)(1-1/10)...(1-1/253)<2/5

Answer 1

de yeu cau gi Phạm Khánh Linh

Answer 2

(1−13)(1−16)...(1−1253)

=23⋅56⋅...⋅252253=46⋅1012⋅...⋅504506

=1⋅42⋅3⋅2⋅53⋅4⋅...⋅21⋅2422⋅23

=1⋅2⋅3⋅42⋅52⋅...⋅212⋅22⋅23⋅242⋅32⋅42⋅...⋅222⋅23=1⋅243⋅22=2466<25