Question

find the sum of thirteen terms of the A.P. 2,4,6,8...............​

Answer 1

Answer:

a=t1=2,d=t2-t1=4-2=2

t13=?

using formula

tn=a+(n-1)d

t13=2+(13-1)2

= 2+12×2

=2+24

t13=26

Answer 2

Answer:

Step-by-step explanation:

a=2

b=4

d=b-a

d =4-2

d =2

n=13

Sum=n/2(2a+(n-1)d)

=13/2(2*2+(13-1)2)

=13/2(4+12*2)

=13/2(4+24)

=13/2(28)

=13/2*28

=42

Sum 13=42

Hope this will help you!!