SOLUTION: the 2nd and 6th terms are 1 and 27.find (a)the first term (b)common difference (c)10th term

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Question 420260: the 2nd and 6th terms are 1 and 27.find (a)the first term (b)common difference (c)10th term
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Arithmetic Series

a%5Bn%5D=a%5B1%5D%2B%28n-1%29%2Ad

a%5B2%5D=a%5B1%5D%2B%282-1%29%2Ad+=+1  | a%5B1%5D=+1+-+d

a%5B6%5D=a%5B1%5D%2B%286-1%29%2Ad+=+27

  (1-d) + 5d = 27

          4d = 26

           d = 26/4 = 13/2   a%5B1%5D=+-11%2F2+

CHECKING our Answer***

a%5B2%5D=+-11%2F2+%2B+13%2F2+=+1