SOLUTION: Write out the first five terms of the sequence given by: ok HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! a_n=n^2-n first n is a subsc. a. 0, 2, 6, 12, 20

Algebra ->  Sequences-and-series -> SOLUTION: Write out the first five terms of the sequence given by: ok HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! a_n=n^2-n first n is a subsc. a. 0, 2, 6, 12, 20       Log On


   

Question 43315: Write out the first five terms of the sequence given by:
ok HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
a_n=n^2-n
first n is a subsc.
a. 0, 2, 6, 12, 20
b. 2, 6, 12, 20, 30
c. 1, 4, 9, 16, 25
d. 0, 3, 8, 15, 24
e. None of the others

Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
The n-th term: a%5Bn%5D=n%5E2-n

First term: a%5B1%5D=1%5E2-1 = 1 - 1 = 0
Second term: a%5B2%5D=2%5E2-2 = 4 - 2 = 2
Third term: a%5B3%5D=3%5E2-3 = 9 - 3 = 6
Fourth term: a%5B4%5D=4%5E2-4 = 16 - 4 = 12
Fifth term: a%5B5%5D=5%5E2-5 = 25 - 5 = 20

Hence the first five terms are 0, 2, 6, 12, 20.
Hence (a) is correct.