Problem

Find the $n$th term $a_{n}$ of the geometric sequence described below, where $r$ is the common ratio.
\[
a_{6}=-1024, r=-4
\]
\[
a_{n}=\square
\]

Answer

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Answer

So, the nth term of the sequence is given by: \(\boxed{a_n = (-4)^{(n-1)}}\)

Steps

Step 1 :Given that the 6th term of the geometric sequence is -1024 and the common ratio is -4, we can use the formula for the nth term of a geometric sequence to find the first term. The formula is \(a_n = a_1 * r^{(n-1)}\)

Step 2 :Substitute the given values into the formula: \(-1024 = a_1 * (-4)^{5}\)

Step 3 :Solve for \(a_1\): \(a_1 = -1024 / -1024 = 1\)

Step 4 :Now that we have \(a_1\), we can substitute it into the formula to find \(a_n\): \(a_n = 1 * (-4)^{(n-1)}\)

Step 5 :So, the nth term of the sequence is given by: \(\boxed{a_n = (-4)^{(n-1)}}\)

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