# Arithmetic Series Help!?

• May 16th 2009, 07:38 AM
MP3
Arithmetic Series Help!?
Hi im having a few problems on this question, may anyone help me?

1. For each series, calculate t10

2+10+18+26+..........

thank you
• May 16th 2009, 07:41 AM
Quote:

Originally Posted by MP3
Hi im having a few problems on this question, may anyone help me?

1. For each series, calculate t10

2+10+18+26+..........

thank you

Use the arithmetic summation formula where a=2 , d=8 . Calculate $T_{10}$by plugging the values in .

$T_{10}=S_{10}-S_9$
• May 16th 2009, 07:43 AM
e^(i*pi)
Quote:

Originally Posted by MP3
Hi im having a few problems on this question, may anyone help me?

1. For each series, calculate t10

2+10+18+26+..........

thank you

An arithmetic sequence has the formula:

$U_n = a + (n-1)d$

where
• $U_n$ is the nth term
• $a = U_1$ is the first term
• $n$ number of terms
• $d$ is the common difference

In your case the common difference is 18-10 = 8
The first term is 2
the number of terms is 10

Sub those in and solve