they give you 5+k, 5, and 5-k and then you have to find the next three in the series...im so confused, help please!
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What has happened between each term
5 + k, and 5 ( a subtraction of k)
5 and 5 - k ( a subtraction of k)
the 4th term, will be the 3rd term minus k
(5 - k) - k = 5 - 2k
the 5th term will be the 4th term minus k
(5 - 2k) - k = 5 - 3k
And the 6th term will be 5 - 4k
5 + k, and 5 ( a subtraction of k)
5 and 5 - k ( a subtraction of k)
the 4th term, will be the 3rd term minus k
(5 - k) - k = 5 - 2k
the 5th term will be the 4th term minus k
(5 - 2k) - k = 5 - 3k
And the 6th term will be 5 - 4k
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The ratio between any 2 successive terms in a geometric series will be the same. That is:
5 / (5 + k) = (5 - k) / 5
Solve for k
5 * 5 = (5 - k) * (5 + k)
25 = 25 - k^2
0 = k^2
k = 0
5 + 0 , 5 , 5 - 0 =>
5 , 5 , 5
What do you think the next 3 terms will be?
5 / (5 + k) = (5 - k) / 5
Solve for k
5 * 5 = (5 - k) * (5 + k)
25 = 25 - k^2
0 = k^2
k = 0
5 + 0 , 5 , 5 - 0 =>
5 , 5 , 5
What do you think the next 3 terms will be?
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This is an arithmetic series: each term is k less than its predecessor.