Question

in an ap
given a = 7, a 13 35 find a where d where a=1st term
do=common difference an=nth term.​

Answer 1

Step-by-step explanation:

given a = 7, a 13 35 find a where d where a=1st term

do=common difference an=nth term.

Answer 2

Answer:

First we need to find the common difference

a1=7

a13=35

So we know that nth term of AP is given by a1+(n-1)d

So 13th term is given by

a13=a1+12d=7+12d=35.

Now d=28/12.

Sum to n terms of AP is given by

Sn=n/2 * (2a1+(n-1)d)

S13=13/2 * (2*7+(13-1)(28/12))

=13/2* (14+28)

=13/2* (42)

=13*21

=273 which is the correct answer for sum upto 13th term of this AP:))

Step-by-step explanation: