Qt - sequences and series

641 views 1 replies

Find the sum to 'n' terms in the following series

1. 1.2 + 2.3 + 3.4 + ...........

2. 2.3.4 + 3.4.5 + ...........

 

Replies (1)

the kth term of the 1st question is k(k+1)= k^2 + k  sum of n terms is n(n+1)(2n+1)/6 + n(n+1)/2 = n(n+1)(n+2)/3

the kth term of the 2nd equation is (k+1)*(k+2)*(k+3) = k^3 + 6k^2 + 11k + 6 sum to n terms is n^2*(n+1)^2/4 + n*(n+1)*(2n+1) + 5.5n*(n+1)+6n = n*(n+5)*(n^2 + 5*n + 10)/4

Leave a Reply

Your are not logged in . Please login to post replies

Click here to Login / Register  

Company
13 July 2026
AVP / VP - PCG Advisory

Workforce Connect

Mumbai

MBA

View Details
Company
16 July 2026
Manager - Finance & Accounts

Aliens Group

Hyderabad

CA Final

View Details
Company
ARTICLESHIP 16 July 2026
Article Assistant

G A R U D & Associates

New Delhi

CA Inter

View Details
Company
ARTICLESHIP 23 July 2026
Article

Gianender & Associates

New Delhi

CA Inter

View Details
Company
ARTICLESHIP 16 July 2026
CA Article

Pipara & Co. LLP.

Mumbai

CA Inter

View Details
Company
23 July 2026
CA Inter

Vikram Jadhav and Company

Pune

CA Inter

View Details
Company
ARTICLESHIP 14 July 2026
Article Assistants

R Shyam and Associates

New Delhi

CA Final

View Details
Company
ARTICLESHIP 15 July 2026
CA Articles

Kinjal H Shah & Co.

Mumbai

CA Foundation

View Details