$A=1.2.3+2.3.4+…+90.91$

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$A=1.2.3+2.3.4+…+90.91$

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Amity 4 years 2020-10-17T23:24:04+00:00 1 Answers 79 views 0

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  1. Giakhanh
    0
    2020-10-17T23:25:21+00:00
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    `A=1.2.3+2.3.4+…………+90.91.92`

    `4A=1.2.3.4+2.3.4.4+…………+90.91.92.4`

    `4A=1.2.3.4+2.3.4.5-1.2.3.4+3.4.5.6-2.3.4.5+………….+90.91.92.93-89.90.91.92`

    `4A=90.91.92.93`

    `A=(90.91.92.93)/4=17518410`

     

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