Question

  Giải nhanh giúp mik

Answer 1

`a)` `(5/7)^(2).(5/7)^(5).5/7`

`=(5/7)^(2+3+1)`

`=(5/7)^8`

`b)` `(3/7)^(2).(9)/(49)`

`=(3/7)^(2).(3/7)^(2)`

`=(3/7)^(2+2)`

`=(3/7)^4`

Answer 2

\(a,\left(\dfrac{5}{7}\right)^2.\left(\dfrac{5}{7}\right)^5.\dfrac{5}{7}=\left(\dfrac{5}{7}\right)^{2+5+1}=\left(\dfrac{5}{7}\right)^8\\ b,\left(\dfrac{3}{7}\right)^2.\dfrac{9}{49}=\left(\dfrac{3}{7}\right)^2.\left(\dfrac{3}{7}\right)^2=\left(\dfrac{3}{7}\right)^{2+2}=\left(\dfrac{3}{7}\right)^4\)