Question 1143446: Harmonic sequence:
2,2/3,2/5,2/7 with solution
What is the next term in the harmonic sequence 1/11,1/15,1/19,1/23,...? With solution
What is the nth term of the harmonic sequence 1/2,1/4,1/6,1/8 with solution
Answer by Edwin McCravy(20060) (Show Source):
You can put this solution on YOUR website! Harmonic sequence:
2,2/3,2/5,2/7 with solution
A harmonic sequence is the sequence of reciprocals of the terms of
an arithmetic sequence.
So we make the corresponding arithmetic sequence by taking reciprocals
of the terms:
1/2, 3/2, 5/2, 7/2, which has a1 = 1/2, and d = 2/2 or 1
If has nth term an=a1+(n-1)d
an=1/2+(n-1)(1)
an=1/2+n-1
an=n-1/2
an=2n/n-1/n
an=(2n-1)/n
So the nth term of the original harmonic sequence is the reciprocal of that:
an=n/(2n-1)
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For the others, form the corresponding arithmetic sequence, and proceed as
above.
Edwin
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