Question

Tìm số nguyên n thỏa mãn: 3³ⁿ⁺¹ = 9ⁿ⁺²

Answer 1

3³ⁿ⁺¹ = 9ⁿ⁺²

3³ⁿ⁺¹ = 3²⁽ⁿ⁺²⁾

3³ⁿ⁺¹ = 3²ⁿ⁺⁴

3n + 1 = 2n + 4

2n - 3n = 1 - 4

-n = -3

n = 3 

Answer 2

\(3^{3n+1}=9^{n+2}=\left(3^2\right)^{2n+2}=2^{4n+4}=>3n+1=4n+4=>n=-3\)

Answer 3

ta có : 9ⁿ⁺²=(3²)ⁿ⁺²=3²⁽ⁿ⁺²⁾=3²ⁿ⁺⁴

3³ⁿ⁺¹=9ⁿ⁺²

=>3³ⁿ⁺¹=3²ⁿ⁺⁴

=>3n+1=2n+4

=>3n-2n=4-1

=>n=3

vậy n=3

Answer 4

8^15 .4^13