SOLUTION: 2,6,10,14....... find the 15th term

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Question 212061This question is from textbook Discovering Advanced Algebra
: 2,6,10,14....... find the 15th term This question is from textbook Discovering Advanced Algebra

Found 2 solutions by Edwin McCravy, Earlsdon:
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
2,6,10,14....... find the 15th term

6-2=4, 10-6=4, 14-10=4

So d=4, a%5B1%5D=2

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

a%5B15%5D=2%2B%2815-1%29%284%29

a%5B15%5D=2%2B%2814%29%284%29

a%5B15%5D=2%2B56

a%5B15%5D=58

Checking:

2,6,10,14,18,22,26,30,34,38,42,46,50,54,58

Edwin

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
2, 6, 10,14,...
This is an arithmetic series. The common difference, d = 14-10 = 4.
To find the fifth term:
a%5Bn%5D+=+a%5Bn-1%5D%2Bd Let n = 5 and d = 4:
a%5B5%5D+=+a%5B4%5D%2B4
a%5B5%5D+=+14%2B4
a%5B5%5D+=+18