SOLUTION: Find the common ratio and write out the first four terms of the geometric sequence 7^n+2/2?

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Question 1126255: Find the common ratio and write out the first four terms of the geometric sequence
7^n+2/2?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

The following solution solves this problem using the formula:
a%5Bn%5D+=+a%5B1%5D+%2A+r%5E%28n-1%29
a%5Bn%5D=7%5E%28n%2B2%29%2F2
a%5Bn%5D=%281%2F2%297%5E%28n%2B2%29
since 7%5E%28n%2B2%29=7%5E3%2A7%5E%28n-1%29, we have
a%5Bn%5D=%287%5E3%2F2%297%5E%28n-1%29
a%5Bn%5D=%28343%2F2%297%5E%28n-1%29
=>a%5B1%5D+=343%2F2
=>a%5B1%5D+=171.5 and r=7

first four terms:
a%5B1%5D+=171.5
a%5B2%5D+=+a%2Ar=%28171.5%297=1200.5
a%5B3%5D+=+a%2Ar%5E2=%28171.5%297%5E2=8403.5
a%5B4%5D+=+a%2Ar%5E3=%28171.5%297%5E3=117649%2F2=58824.5