the first term of a geometric sequence is 6 and the common ratio is -8.

1) create an equation for the situation
2) find the 7th term of the sequence

1 answer

  1. In a geometric sequence, the \( n \)-th term can be represented as:

\[ a_n = a_1 \cdot r^{(n-1)} \]

where:

  • \( a_n \) is the \( n \)-th term,
  • \( a_1 \) is the first term,
  • \( r \) is the common ratio,
  • \( n \) is the term number.

For this situation, the first term \( a_1 = 6 \) and the common ratio \( r = -8 \). Therefore, the equation for the \( n \)-th term of the sequence is:

\[ a_n = 6 \cdot (-8)^{(n-1)} \]

  1. To find the 7th term of the sequence \( a_7 \):

\[ a_7 = 6 \cdot (-8)^{(7-1)} = 6 \cdot (-8)^6 \]

Now, we calculate \( (-8)^6 \):

\[ (-8)^6 = 262144 \]

So,

\[ a_7 = 6 \cdot 262144 = 1572864 \]

Thus, the 7th term of the sequence is:

\[ \boxed{1572864} \]