**Problem 7:** Find the sum of the first \( n \) triangular numbers. (Hint: Show first that each triangular number can be represented as \( T_n = \frac{n^2 + n}{2} = \frac{1}{2}(n^2 + n) \).

Find the sum of first n triangular numbers

Answered: Problem 7. Find the sum of the first n…

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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Problem 7. Find the sum of the first n triangular numbers (Hint: Show first that each triangular number can be n²+n represented as Tn 2 = = 1/10 2 n² + n). (