tính hộ em với : 1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

Question

tính hộ em với : 1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

in progress 0
Calantha 4 years 2020-11-06T01:43:18+00:00 2 Answers 201 views 0

Answers ( )

  1. Nho
    1
    2020-11-06T01:44:26+00:00
    Reply

    Giải thích các bước giải:

    `1−5/6+7/12−9/20+11/30−13/42+15/56−17/72+19/90`

    `=1−5/(2×3)+7/(3×4)−9/(4×5)+11/(5×6)−13/(6×7)+15/(7×8)−17/(8×9)+10/(9×10)`

    `=1−1/2−1/3+1/3+1/4−1/4−1/5+1/5+1/6−1/6−1/7+1/7+1/8−1/8−1/9+1/9+1/10`

    `=1−1/2+1/10=1/2+1/10=6/10=3/5`

  2. Eirian
    0
    2020-11-06T01:45:07+00:00
    Reply

    1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90

    =(10080-5×1680+7×840-9×504+11×336-13×240+15×180-17×140+19×112)/10080

    =3/5

    XIN CÂU TRẢ LỜI HAY NHẤT

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )