SOLUTION: how do you solve this problem using recuesive rules? 45,15,5,5/3,5/9

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Question 873318: how do you solve this problem using recuesive rules? 45,15,5,5/3,5/9
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the differences between successive terms,
A%5B2%5D=A%5B1%5D%2F3
A%5B3%5D=A%5B2%5D%2F3
etc.
so
A%5Bn%5D=45%2A%281%2F3%29%5E%28n-1%29

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
45,15,5,5/3,5/9
r = 1/3
++a%5Bn%5D+=+a%5B1%5Dr%5E%28n+-+1%29%0D%0A%7B%7B%7Ba%5Bn%5D+=+45%281%2F3%29%5E%28n-1%29
S%5Bn%5D+=+a%5B1%5D%281-r%5En%29%2F%281-r%29+
S%5B5%5D+=+45%281-%281%2F3%29%5E5%29%2F%282%2F3%29