we have 3^x +3 x (1/9)^x-1 = 1
Remember 3 is a factor of 9 and 9 = 3^2
Therefore, 1/9 = 1/3^2
we can rewrite the above equation as
3^x + 3 x (1/3^2)^x-1 = 1
We have some rule of indicies guiding this equation
x^-a = 1/x^a
this means that 1/3^2 can also be written as 3^-2
i.e 1/3^2 = 3^-2
put 3^-2 to replace 1/3^2
= 3^x + 3 x (3^-2)^x-1 = 1
Let us check another rule
x^0 = 1
3^x + 3^1
