IDNLearn.com is designed to help you find the answers you need quickly and easily. Discover trustworthy solutions to your questions quickly and accurately with help from our dedicated community of experts.

Predict the general term, or nth term, [tex]a_n[/tex], of the sequence.

[tex]\[
-10, 50, -250, 1250, -6250, \ldots
\][/tex]

[tex]\[
a_n = \square
\][/tex]

(Simplify your answer.)


Sagot :

To determine the general term [tex]\(a_n\)[/tex] of the sequence [tex]\(-10, 50, -250, 1250, -6250, \ldots\)[/tex], we will follow these steps:

1. Identify the first term [tex]\((a_1)\)[/tex]:
The first term of the sequence is [tex]\(a_1 = -10\)[/tex].

2. Determine the common ratio [tex]\((r)\)[/tex]:
To find the common ratio, divide the second term by the first term:
[tex]\[ r = \frac{50}{-10} = -5 \][/tex]
Verify the common ratio with the next terms:
[tex]\[ \frac{-250}{50} = -5 \quad \text{and} \quad \frac{1250}{-250} = -5 \][/tex]
The common ratio [tex]\(r\)[/tex] is consistently [tex]\(-5\)[/tex].

3. Formulate the general term for a geometric sequence:
The general formula for the nth term of a geometric sequence is given by:
[tex]\[ a_n = a_1 \cdot r^{(n-1)} \][/tex]
Plugging in the values for [tex]\(a_1\)[/tex] and [tex]\(r\)[/tex]:
[tex]\[ a_n = -10 \cdot (-5)^{(n-1)} \][/tex]
This provides the simplified general term of the sequence.

Therefore, the general term [tex]\(a_n\)[/tex] of the given sequence is:
[tex]\[ a_n = -10 \cdot (-5)^{(n-1)} \][/tex]