Question

If the sum of first n terms of an AP is given by 6n + 7n2. Find the 10th term of the AP.

Answer 1

Answer:

Step-by-step explanation:

S

n

​

=6n+7n

2

If n=1,

S

1

​

=6+7=13

S

2

​

=6(2)+7(4)=40

a

1

​

=13=a

a

1

​

+a

2

​

=40

a+a+d=40

2a+d=40

2×13+d=40

d=14.

a

10

​

=a+9d=13+126=139