Arithmetic Sequence

Question

Find the 17 ^th term of the arithmetic sequence –5, 1, 7, 13, …

Answer 1

Given AP -5, 1, 7, 13...........

t1  =  a  =  -5

t2  =  1

d  =  t2 - t1

    =  1  -  (-5)

    =  1 + 5

d  =  6

nth term tn = a + (n-1)d --------------> (1)

Substitute a  =  - 5 and d  =  6 and n = 17 in Eq (1)

t17  =  -5 + (17 - 1)6 

       =  -5 + (16)6

       =  -5 + 96

t17  = 91.

Answer :

The 17th term is 91.