Looking for answers? Westonci.ca is your go-to Q&A platform, offering quick, trustworthy responses from a community of experts. Discover in-depth answers to your questions from a wide network of experts on our user-friendly Q&A platform. Join our Q&A platform to connect with experts dedicated to providing accurate answers to your questions in various fields.

Complete the following sums by filling in the missing sections appropriately.

1. [tex]\[ 12 + 16 + 20 + 24 + \cdots = \sum_{n=1}^{10} (8 + 4n) \][/tex]

2. [tex]\[ 13 + 17 + 21 + 25 + \cdots + 57 = \sum_{n=1}^{12} (5 + 4n) \][/tex]

3. [tex]\[
\begin{array}{r}
8 + 11 + 14 + 17 + \cdots + 29 = \sum_{n=2}^{8} (5 + 3n) \\
\hline
\end{array}
\][/tex]

4. [tex]\[ 12 + 15 + 18 + 21 + \cdots + 39 = \sum_{n=1}^{10} (3 + 3n) \][/tex]


Sagot :

Sure! Let's complete and solve each series step-by-step.

### 1. Series: [tex]\[12 + 16 + 20 + 24 + \ldots = \sum_{n=1}^{10} (8 + 4n)\][/tex]

We need to determine the series and then find the sum:

1. For [tex]\( n=1 \)[/tex]: [tex]\( 8 + 4 \cdot 1 = 8 + 4 = 12 \)[/tex]
2. For [tex]\( n=2 \)[/tex]: [tex]\( 8 + 4 \cdot 2 = 8 + 8 = 16 \)[/tex]
3. For [tex]\( n=3 \)[/tex]: [tex]\( 8 + 4 \cdot 3 = 8 + 12 = 20 \)[/tex]
4. For [tex]\( n=4 \)[/tex]: [tex]\( 8 + 4 \cdot 4 = 8 + 16 = 24 \)[/tex]
5. [tex]\(\vdots\)[/tex]
6. For [tex]\( n=10 \)[/tex]: [tex]\( 8 + 4 \cdot 10 = 8 + 40 = 48 \)[/tex]

So, the sequence is: 12, 16, 20, 24, 28, 32, 36, 40, 44, 48.

Now, summing these terms:
[tex]\[ 12 + 16 + 20 + 24 + 28 + 32 + 36 + 40 + 44 + 48 = 300 \][/tex]

### 2. Series: [tex]\[13 + 17 + 21 + 25 + \ldots + 57 = \sum (5 + 4n)\][/tex]

To find the series and its sum:

1. For [tex]\( n=2 \)[/tex]: [tex]\( 5 + 4 \cdot 2 = 5 + 8 = 13 \)[/tex]
2. For [tex]\( n=3 \)[/tex]: [tex]\( 5 + 4 \cdot 3 = 5 + 12 = 17 \)[/tex]
3. For [tex]\( n=4 \)[/tex]: [tex]\( 5 + 4 \cdot 4 = 5 + 16 = 21 \)[/tex]
4. [tex]\(\vdots\)[/tex]
5. For [tex]\( n=14 \)[/tex]: [tex]\( 5 + 4 \cdot 14 = 5 + 56 = 61 \)[/tex]

So, the sequence is: 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61.

Now, summing these terms:
[tex]\[ 13 + 17 + 21 + 25 + 29 + 33 + 37 + 41 + 45 + 49 + 53 + 57 + 61 = 481 \][/tex]

### 3. Series: [tex]\[8 + 11 + 14 + 17 + \ldots + 29 = \sum_{n=2}\][/tex]

To find the series and its sum:

1. For [tex]\( n=0 \)[/tex]: [tex]\( 8 + 3 \cdot 0 = 8 + 0 = 8 \)[/tex]
2. For [tex]\( n=1 \)[/tex]: [tex]\( 8 + 3 \cdot 1 = 8 + 3 = 11 \)[/tex]
3. For [tex]\( n=2 \)[/tex]: [tex]\( 8 + 3 \cdot 2 = 8 + 6 = 14 \)[/tex]
4. [tex]\(\vdots\)[/tex]
5. For [tex]\( n=7 \)[/tex]: [tex]\( 8 + 3 \cdot 7 = 8 + 21 = 29 \)[/tex]

So, the sequence is: 8, 11, 14, 17, 20, 23, 26, 29.

Now, summing these terms:
[tex]\[ 8 + 11 + 14 + 17 + 20 + 23 + 26 + 29 = 148 \][/tex]

### 4. Series: [tex]\[12 + 15 + 18 + 21 + \ldots + 39 = \sum (3 + 3n)\][/tex]

To find the series and its sum:

1. For [tex]\( n=4 \)[/tex]: [tex]\( 3 + 3 \cdot 4 = 3 + 12 = 15 \)[/tex]
2. For [tex]\( n=5 \)[/tex]: [tex]\( 3 + 3 \cdot 5 = 3 + 15 = 18 \)[/tex]
3. For [tex]\( n=6 \)[/tex]: [tex]\( 3 + 3 \cdot 6 = 3 + 18 = 21 \)[/tex]
4. [tex]\(\vdots\)[/tex]
5. For [tex]\( n=11 \)[/tex]: [tex]\( 3 + 3 \cdot 11 = 3 + 33 = 36 \)[/tex]

So, the sequence is: 15, 18, 21, 24, 27, 30, 33, 36.

Now, summing these terms:
[tex]\[ 15 + 18 + 21 + 24 + 27 + 30 + 33 + 36 = 204 \][/tex]

Therefore, the completed series and sums are as follows:

1. [tex]\(12, 16, 20, 24, 28, 32, 36, 40, 44, 48 = \sum (8 + 4n) = 300\)[/tex]
2. [tex]\(13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61 = \sum (5 + 4n) = 481\)[/tex]
3. [tex]\(8, 11, 14, 17, 20, 23, 26, 29 = \sum_{n=2} = 148\)[/tex]
4. [tex]\(15, 18, 21, 24, 27, 30, 33, 36 = \sum (3 + 3n) = 204\)[/tex]
Thank you for your visit. We're dedicated to helping you find the information you need, whenever you need it. Thank you for visiting. Our goal is to provide the most accurate answers for all your informational needs. Come back soon. Thank you for visiting Westonci.ca, your go-to source for reliable answers. Come back soon for more expert insights.