Question

Find the first four terms of the sequence defined below, where n represents the position of a term in the sequence. Start with n = 1.

an = 9n

Answer 1

To find the first four terms of the sequence defined by the formula \( a_n = 9n \), we can substitute \( n \) with the values 1 through 4:

1. For \( n = 1 \):
\[
a_1 = 9 \cdot 1 = 9
\]

2. For \( n = 2 \):
\[
a_2 = 9 \cdot 2 = 18
\]

3. For \( n = 3 \):
\[
a_3 = 9 \cdot 3 = 27
\]

4. For \( n = 4 \):
\[
a_4 = 9 \cdot 4 = 36
\]

Thus, the first four terms of the sequence are:
- \( a_1 = 9 \)
- \( a_2 = 18 \)
- \( a_3 = 27 \)
- \( a_4 = 36 \)

In summary, the first four terms are: **9, 18, 27, 36**.