若3^n+1*5^n+1=15^2n-7,则n=多少

问题描述:

若3^n+1*5^n+1=15^2n-7,则n=多少

3^n+1*5^n+1=15^2n-7
15^(n+1)=15^(2n-7)
n+1=2n-7
n=8.