SOLUTION: find a1 and the common ratio(r). given an=1, n=7, sn=1

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Question 934991: find a1 and the common ratio(r). given an=1, n=7, sn=1
Answer by MathLover1(20850)   (Show Source): You can put this solution on YOUR website!
find and the common ratio()if given , ,
we know that
...plug in given values

...solve for in terms of
...........eq.1

we also know that the sum is:
...plug in given values
.........solve for





go to .....eq.1 plug in



....reduce, divide both numerator and denominator by


check:






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