Problem 56

Question

Express each sum using summation notation. Use a lower limit of summation of your choice and k for the index of summation. $$6+8+10+12+\dots+32$$

Step-by-Step Solution

Verified
Answer
The series \(6+8+10+12+...+32\) can be written in summation notation as \(\sum_{k=1}^{14} (4 + 2k)\).
1Step 1: Identify the Common Difference
The numbers in the series are increasing by 2, therefore the common difference, \(d\), is 2.
2Step 2: Identify the First Term
The first term in this arithmetic series, \(a_1\), is 6.
3Step 3: Determine the General Term
The general form of an arithmetic sequence is \(a_k = a_1 + (k - 1)d\), where \(a_k\) is the value of the term at position \(k\), \(a_1\) is the first term, \(d\) is the common difference, and \(k\) is the position. In this case, the arithmetic sequence is \(a_k = 6 + (k - 1)2 = 4 + 2k\).
4Step 4: Write in Summation Notation
The series can now be written in summation notation as \(\sum_{k=1}^{14} (4 + 2k)\)