HELP ME: a)7/19.8/11+7/19.3/11+12/19 b)17/13.18/23-4/13.18/23- -5/23 c)5/7.-4/19+-15/7.5/19

0 bình luận về “HELP ME: a)7/19.8/11+7/19.3/11+12/19 b)17/13.18/23-4/13.18/23- -5/23 c)5/7.-4/19+-15/7.5/19”

1. Đáp án:

    

   Giải thích các bước giải:

    `7/19. 8/11+7/19. 3/11+12/19`

   `= 7/19. (8/11 + 3/11) + 12/19`

   `= 7/19. 1 + 12/19`

   `= 7/19 + 12/19`

   `=1`

   `17/13. 18/23 – 4/13. 18/23- (-5)/23`

   `= 18/23. (17/13 – 4/13) + 5/23`

   `= 18/23. 1 + 5/23`

   `= 18/23 + 5/23`

   `=1`

   `5/7. -4/19+ -15/7. 5/19`

   `= -20/133 + -75/133`

   `= -5/7`

   Bình luận

2. a) `7/19. 8/11+7/19. 3/11+12/19`

   `= 7/19. (8/11 + 3/11) + 12/19`

   `= 7/19. 1 + 12/19`

   `= 7/19 + 12/19`

   `= 1`

   b) `17/13. 18/23 – 4/13. 18/23- -5/23`

   `= 18/23. (17/13 – 4/13) + 5/23`

   `= 18/23. 1 + 5/23`

   `= 18/23 + 5/23`

   `= 1`

   c) `5/7. -4/19+ -15/7. 5/19`

   `= (5. -4)/(7. 19) + (-15. 5)/(7. 19)`

   `= -20/133 + -75/133`

   `= -95/133`

   `= -5/7`

   Bình luận