Question

the first term of an arthematic sequence is 7 and the common difference is-2 what is the 12th term​

Answer 1

Answer:

We have,

a= First term =−7 and, d= Common difference =5

a

18

=a+(18−1)d [∵a

n

=a+(n−1)d]

⟹a

18

=a+17d=−7+17×5=78

and the general term a

n

=a+(n−1)×5=−7+(n−1)×5

⟹a

n

=−7+5n−5=5n−12