2 mũ 2 . 85 + 15 . 2 mũ 2 – 2021mũ0 -2/9 – (7/3-3/9+7/4)+5/4

2 bình luận về “2 mũ 2 . 85 + 15 . 2 mũ 2 – 2021mũ0 -2/9 – (7/3-3/9+7/4)+5/4”

1. 2^2 . 85 + 15 . 2^2 – 2021^0

   = 4 . 85 + 15 . 4 – 1

   = 4 . (85 + 15) – 1

   = 4 . 100 – 1

   = 400 – 1

   = 399

   ———–

   (-2)/9 – (7/3 – 3/9 + 7/4) + 5/4

   = (-2)/9 – (84/36 – 12/36 + 63/36) + 5/4

   = (-2)/9 – 15/4 + 5/4

   = (-8)/36 – 135/36 + 45/36

   = ((-8) -135+45)/36

   = (-98)/36 = (-49)/18

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   Trả lời
2. 2^2 . 85 + 15 . 2^2 – 2021^0

   = 4 . 85 + 15 . 24 – 1

   = 4 . ( 85 + 15 ) – 1

   = 4 . 100 – 1

   = 400 – 1

   = 399

   ——–

   -2/9 – (7/3-3/9+7/4)+5/4

   = -2/9 – ( 84/36 – 12/36 + 63/36 ) + 5/4

   = -2/9 – 15/4 + 5/4

   = -8/36 – 135/36 + 45/36

   = -98/36 = -49/18

    

   Trả lời