5/9*7/13+5/9*8/13-5/13*2/9

Đáp án+Giải thích các bước giải:

  $\frac{5}{9}$ . $\frac{7}{13}$ + $\frac{5}{9}$ . $\frac{8}{13}$ - $\frac{5}{13}$ . $\frac{2}{9}$

= $\frac{5}{9}$ . ($\frac{7}{13}$ + $\frac{8}{13}$ ) - $\frac{5}{13}$ . $\frac{2}{9}$

= $\frac{5}{9}$ . $\frac{15}{13}$  - $\frac{5}{13}$ . $\frac{2}{9}$

= $\frac{25}{39}$ - $\frac{10}{117}$

= $\frac{5}{9}$

Xin ctlhn cho nhs ạ :>

$#anime2k10$

`5/9. 7/13 + 5/9. 8/13 - 5/13. 2/9`

`= 5/9. 7/13 + 5/9. 8/13 - {5.2}/{13.9}`

`= 5/9. 7/13 + 5/9. 8/13 - 5/9. 2/13`

`= 5/9. ( 7/13 + 8/13 - 2/13 )`

`= 5/9. 1`

`= 5/9`