Question

Tính   (3/7)^21 : (9/49)^6

Answer 1

(3/7)^21:[(3/7)^2]^6

(3/7)^21:[(3/7)^12

(3/7)^21-12

^{(3/7)^9}

 

Answer 2

(3/7)²¹: (9/49)⁶

= (3/7)²¹: (3²/7²)⁶

= (3/7)²¹: (3/7)¹²

= (3/7)^21-12

= (3/7)⁹

Answer 3

=(3/7)^9 lol