The Total solution for NCERT class 6-12
1.2.4 + 2.3.7 + 3.4.10 + … to n terms.
Let Tn bethe nth term of the given series.We have:
Tn = n(n + 1) (3n + 1)
= n (3n2 +4n + 1)
= 3n3 +4n2 + n
Now, let Sn bethe sum of n terms of the given series.We have:
∴ The sum of the seriesis
