A = 1/1×2+1/2×3+1/3×4+…..+1/99×100

Question

A = 1/1×2+1/2×3+1/3×4+…..+1/99×100

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Sigridomena 4 years 2020-10-31T06:19:26+00:00 2 Answers 99 views 0

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    0
    2020-10-31T06:20:33+00:00

    Đáp án:

     `A=99/100`

    Giải thích các bước giải:

    `A = 1/(1.2) + 1/(2.3) + 1/(3.4) + . . . + 1/(99.100)`

    `A= 1/1-1/2+1/2-1/3+1/3-1/4+….+1/99-1/100`

    `A=1-1/100`

    `A=99/100`

    0
    2020-10-31T06:20:48+00:00

    $A$ $=$ $\frac{1}{1.2}$ $+$ $\frac{1}{2.3}$ $+$ $\frac{1}{3.4}$ $+$ $…$ $+$ $\frac{1}{99.100}$ 

            $=$ $1$ $-$ $\frac{1}{2}$ $+$ $\frac{1}{2}$ $-$ $\frac{1}{3}$ $+$ $\frac{1}{3}$ $-$ $\frac{1}{4}$ $+$ $…$ $+$ $\frac{1}{9}$ $-$ $\frac{1}{100}$ 

             $=$ $1$ $-$ $\frac{1}{100}$ $=$ $\frac{99}{100}$ 

     

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