1. ## Arithmetic sequences

For the arithmetic sequence with given first term 2 and common difference 3:
its th term is ;
its 10-th term is .

I am not sure how to proceed I thought the nth term would be 3n and the 10th term 30 but I was wrong?

2. ## Re: Arithmetic sequences

r is the common difference:

$a_n=a_1+(n-1)r=2+3(n-1)=3n-1$

$a_{10}=a_1+9r=2+27=29$

3. ## Re: Arithmetic sequences

Ok now I understand it abit more thank you
and nice use of LaTeX