3^(n+1)-3^(n-2)

Need help simplifying this please.

3 answers

because multiplication of powers results in adding exponents, one can reduce this to

3^n*3^1 - 3^n*3^-2

3^n * (3-1/9)=3^n (2 8/9)
still don't really quite understand. could you explain your process a bit more?
Mara -- why are you butting in to richard's question?