SOLUTION: How to simplify: {3^{n+2} - 3^n + 15{3^{n-1}} }/39

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Question 974620: How to simplify:
{3^{n+2} - 3^n + 15{3^{n-1}} }/39
Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!

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%283%5E%28n%2B2%29+-+3%5En+%2B+15%283%5E%28n-1%29%29%29%2F39=3%5En%2A%2813%2F39%29
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%283%5E%28n%2B2%29+-+3%5En+%2B+15%283%5E%28n-1%29%29%29%2F39=3%5En%2A%281%2F3%29
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%283%5E%28n%2B2%29+-+3%5En+%2B+15%283%5E%28n-1%29%29%29%2F39=3%5E%28n-1%29

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

How to simplify:
{3^{n+2} - 3^n + 15{3^{n-1}} }/39
%283%5E%28n+%2B+2%29+-+3%5En+%2B+15%283%5E%28n+-+1%29%29%29%2F39

%283%5E%28n+-+1%29+%2A+%283%5E3+-+3%5E1+%2B+15%29%29%2F39 ------- Factoring out GCF, 3%5E%28n+-+1%29 in numerator

%283%5E%28n+-+1%29%2A%2827+-+3+%2B+15%29%29%2F39

%283%5E%28n+-+1%29%2A%2839%29%29%2F39

%283%5E%28n+-+1%29%2Across%28%2839%29%29%29%2Fcross%2839%29_______highlight_green%283%5E%28n+-+1%29%29