Write down the first 5 terms of the sequence given by each of these algebraic expressions:




$3 n+1$
4n2n-1$5 n +2$


\_\_\_\_
\_\_\_\_\_\_\_\_\_\_\_\_

1
111

2
222

3
333

4
444

5
555






What is the 10th term of the sequence $2 n+1$?
What is the 8th term of the sequence $6 n+3$?What is the 5th term of the sequence $4 n+1$?


Verified Answer :

  • Calculate terms by substituting \(n=1\) through \(5\) into the expressions to find the first five terms of each sequence.
  • Find specific sequence terms by substituting the given position number \(n\) directly into the expression.
  • Sequences: \(3n+1 \rightarrow 4, 7, 10, 13, 16\); \(4n \rightarrow 4, 8, 12, 16, 20\); \(2n-1 \rightarrow 1, 3, 5, 7, 9\); \(5n+2 \rightarrow 7, 12, 17, 22, 27\).
  • Specific terms: 10th of \(2n+1\) is \(\boxed{21}\), 8th of \(6n+3\) is \(\boxed{51}\), 5th of \(4n+1\) is \(\boxed{21}\).

Explanation

  1. Understanding Sequence Calculation

The objective is to find the first five terms of four different algebraic sequences and to find specific terms for three other sequences. An algebraic expression for a sequence allows us to calculate any term by substituting the position number, denoted by \(n\), into the expression. For the first part, we calculate terms for \(n=1, 2, 3, 4, 5\). For the second part, we substitute specific values of \(n\) to find the requested terms.

  1. Calculating the First Five Terms

To find the first five terms of each sequence, we substitute \(n = 1, 2, 3, 4, 5\) into the expressions:

  • For \(3n+1\):
  • \(n=1: 3(1)+1 = 4\)
  • \(n=2: 3(2)+1 = 7\)
  • \(n=3: 3(3)+1 = 10\)
  • \(n=4: 3(4)+1 = 13\)
  • \(n=5: 3(5)+1 = 16\)
  • For \(4n\):
  • \(n=1: 4(1) = 4\)
  • \(n=2: 4(2) = 8\)
  • \(n=3: 4(3) = 12\)
  • \(n=4: 4(4) = 16\)
  • \(n=5: 4(5) = 20\)
  • For \(2n-1\):
  • \(n=1: 2(1)-1 = 1\)
  • \(n=2: 2(2)-1 = 3\)
  • \(n=3: 2(3)-1 = 5\)
  • \(n=4: 2(4)-1 = 7\)
  • \(n=5: 2(5)-1 = 9\)
  • For \(5n+2\):
  • \(n=1: 5(1)+2 = 7\)
  • \(n=2: 5(2)+2 = 12\)
  • \(n=3: 5(3)+2 = 17\)
  • \(n=4: 5(4)+2 = 22\)
  • \(n=5: 5(5)+2 = 27\)
  1. Finding Specific Sequence Terms

Now we find the specific terms requested by substituting the given \(n\) values:

  • The 10th term of \(2n+1\):
  • Substitute \(n=10\): \(2(10)+1 = 20+1 = 21\)
  • The 8th term of \(6n+3\):
  • Substitute \(n=8\): \(6(8)+3 = 48+3 = 51\)
  • The 5th term of \(4n+1\):
  • Substitute \(n=5\): \(4(5)+1 = 20+1 = 21\)
  1. Conclusion

In summary, we have calculated the sequences and specific terms as follows:

  • The first five terms for \(3n+1\) are \(4, 7, 10, 13, 16\).
  • The first five terms for \(4n\) are \(4, 8, 12, 16, 20\).
  • The first five terms for \(2n-1\) are \(1, 3, 5, 7, 9\).
  • The first five terms for \(5n+2\) are \(7, 12, 17, 22, 27\).
  • The 10th term of \(2n+1\) is \(21\).
  • The 8th term of \(6n+3\) is \(51\).
  • The 5th term of \(4n+1\) is \(21\).

Examples

Algebraic sequences are used in many real-life situations, such as calculating savings or planning projects. For example, if you start a piggy bank with \$2 and add \$3 each week, the amount in the bank after \(n\) weeks can be represented by the sequence \(3n+2\). After 5 weeks, you would have \(3(5)+2 = \$17\). Understanding these patterns helps you predict outcomes and manage resources effectively.