How do you write a rule for the nth term of the arithmetic sequence given d=2, #a_1=5#?

1 Answer
Jul 18, 2016

#a_n=2n+3#

Explanation:

The terms in the standard #color(blue)"Arithmetic sequence"# are

#a,a+d,a+2d,a+3d, ...... ,a+(n-1)d#

where a is the 1st term, d, the common difference and the nth term is a + (n -1)d

Each term in the sequence is obtained by adding d to the previous term.

Using the nth term, that is a + (n -1)d

with a = 5 and d = 2

#rArra_n=5+2(n-1)=5+2n-2=2n+3#