Skip to main content
Ch. 8 - Sequences, Induction, and Probability
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 9, Problema 45

Write out the first three terms and the last term. Then use the formula for the sum of the first n terms of an arithmetic sequence to find the indicated sum.
∑i=117(5i+3)\(\sum\)_{i=1}^{17} (5i + 3)

Guida verificata passo dopo passo
1
Identify the arithmetic sequence given by the general term \(a_i = 5i + 3\), where \(i\) ranges from 1 to 17.
Find the first three terms by substituting \(i = 1, 2, 3\) into the formula: \(a_1 = 5(1) + 3\), \(a_2 = 5(2) + 3\), \(a_3 = 5(3) + 3\).
Find the last term by substituting \(i = 17\) into the formula: \(a_{17} = 5(17) + 3\).
Recall the formula for the sum of the first \(n\) terms of an arithmetic sequence: \(S_n = \frac{n}{2} (a_1 + a_n)\), where \(n\) is the number of terms, \(a_1\) is the first term, and \(a_n\) is the last term.
Substitute \(n = 17\), the first term \(a_1\), and the last term \(a_{17}\) into the sum formula to express the sum \(S_{17}\) without calculating the final value.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
4m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Arithmetic Sequence

An arithmetic sequence is a list of numbers where each term after the first is found by adding a constant difference to the previous term. For example, in the sequence defined by 5i + 3, the difference between consecutive terms is constant (5). Understanding this helps identify the terms and their pattern.
Video consigliato:
5:17
Arithmetic Sequences - General Formula

Sum of the First n Terms of an Arithmetic Sequence

The sum of the first n terms of an arithmetic sequence can be found using the formula S_n = n/2 (a_1 + a_n), where a_1 is the first term and a_n is the nth term. This formula simplifies the process of adding many terms without listing them all.
Video consigliato:
5:17
Arithmetic Sequences - General Formula

Evaluating Summation Notation

Summation notation (Σ) represents the sum of terms defined by a formula over a range of indices. Here, it sums the expression 5i + 3 from i = 1 to 17. Understanding how to interpret and expand this notation is essential for finding specific terms and the total sum.
Video consigliato:
05:18
Interval Notation