Question

find the first twenty terms of arithmetic series 2+7+12+.....using suitable formula​

Answer 1

Answer:

a=2

d=7-2=5

n=4th term

By applying formula of n,

nth term=a+(n-1)d

4th term=2+(4-1)×5

=2+15

=17

and so on..........................

For sum of 20 term apply this given formula,

Sum=n/2×(2a+(n-1)d)

Step-by-step explanation:

Answer 2

Answer:

2,7,12,17,22,27,32,37,42,47,52,47,52,57,62,67,72,77,82,87

Step-by-step explanation:

a=2,d=5,t2=7,t3=12

t4=t3+d

=17......................