`1/(1xx2) + 1/(2xx3) + 1/(3xx4) +...+ 1/(99xx100)`
`= (2-1)/(1xx2) + (3-2)/(2xx3) + (4-3)/(3xx4) +...+ (100-99)/(99xx100)`
`= 1/1 - 1/2 + 1/2 - 1/3 + 1/3 - 1/4 +...+ 1/99-1/100`
`= 1/1 - 1/100`
`= 100/100 - 1/100`
`= 99/100`
Đáp án:
99/100
Giải thích các bước giải:
(1/1×2)+ (1/2×3)+ (1/3×4)+...+ (1/99×100)
=1-1/2+1/2-1/3+1/3-1/4+...+ 1/99-1/100
=1+(-1/2+1/2)+(-1/3+1/3)+(-1/4+1/4)+...+(-1/99+ 1/99)-1/100
=1-1/100
=99/100
vậy tổng trên bằng 99/100
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I know the guitarist _________ is performing on the stage A. which B. Whose C. he D. that Chọn đáp án và giải thích cho mình hiểu được kh ạ Phân vân quá ạ :))
Giải chi tiết,cụ thể giúp mình nhé
Bệnh máu khó đông do gen lặn h nằm trên nst giới tính x puy đinh hay cho biết ai mặc bệnh nhiều hơn và vì sao
vai trò của khu lưu niêm trần phú
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Cho hình chóp tứ giác đều. Biết cạnh đáy 4 cm cạnh bên 5 cm đường cao 3 cm . Tính diện tích xung quanh diện tích toàn phần thể tích của hình chóp.
một khối hình lập phương có cạnh 4 (cm) được thả vào nước thì thấy chìm 3/4 trong nước biết (D nước = 1000kg/m^3). tính lực đẩy Acsimet tác dungj lên khối gỗ đó là:
Có người cho rằng, thơ Bác là bức chân dung tinh thần tự họa. Qua bài thơ RẰM THÁNG GIÊNG, em hãy nêu rõ vẻ đẹp của bức chân dung tự họa ấy.
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