yang c kira kira brp ya ?

[tex] \sqrt[4]{9}^{x+1}=81[/tex]
[tex]\sqrt[4]{3}^{(x+1)2}=3 ^{3}[/tex]
[tex]\sqrt[2]{3}^{(x+1)}=3 ^{3}[/tex]
[tex]{3}^ \frac{x+1}{2}=3 ^{3}[/tex]
[tex] \frac{x+1}{2} = 3[/tex]
x+1=6
x=5

9^(x + 1)/4 = 81
3^2(x + 1)/4 = 3^4
3^(x + 1)/2 = 3^4
(x + 1)/2 = 4
x + 1 = 8
x = 7