SOLUTION: I need help on this homework problem. Thank you for any help you can provide.
a1=1 r=-1 find s20
I keep getting 1 as the answer but the answer is 0. what am I missing?
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Sequences-and-series
-> SOLUTION: I need help on this homework problem. Thank you for any help you can provide.
a1=1 r=-1 find s20
I keep getting 1 as the answer but the answer is 0. what am I missing?
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Question 63561: I need help on this homework problem. Thank you for any help you can provide.
a1=1 r=-1 find s20
I keep getting 1 as the answer but the answer is 0. what am I missing? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! a1=1 r=-1 find s20
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S(n)= a(1)[r^(n+1)-1]/ [r-1]
S(20)= 1[[(-1)^(21)-1]/[-1-1]
S(20)= [-1-1]/[-1-1]=1
You are correct.
Cheers,
Stan H.
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