Question

Задана числовая последовательность {an}: an = 4n * n + 5 Найдите 1, 3, 6 и 10 члены последовательности.

Answer 1

$a_1=4\cdot 1\cdot 1+5=4+5=9\\ a_3=4\cdot 3\cdot 3+5=41\\ a_6=4\cdot 6\cdot 6+5=149\\ a_{10}=4\cdot 10\cdot 10+5=405$

Answer 2

To find the 1st, 3rd, 6th, and 10th terms of the sequence {an} defined as an = 4n * n + 5, we'll substitute the values of n into the expression for 'an'. Let's calculate each term:

1. For n = 1: a1 = 4 * 1 * 1 + 5 = 4 + 5 = 9

2. For n = 3: a3 = 4 * 3 * 3 + 5 = 36 + 5 = 41

3. For n = 6: a6 = 4 * 6 * 6 + 5 = 144 + 5 = 149

4. For n = 10: a10 = 4 * 10 * 10 + 5 = 400 + 5 = 405

So, the 1st term (a1) is 9, the 3rd term (a3) is 41, the 6th term (a6) is 149, and the 10th term (a10) is 405 in the sequence {an}.