Question

Write A= "3,9,27,81"in set builder form

Answer 1

set builder form can be
{x:x is x^n , n is 1《 n 《4 }
because 3=3^1 , 9=3^2 , 27 =3^3 , 81 = 3^4
${ \: x: x \: is \: x ^{n} . and \: n \: is \: 1 \leqslant n \leqslant 4 \: }$