Verified Answer :

caylus

Hello,
\(u_{1}=3\)
\(u_{2}=3*(-4)\)
\(u_{3}=3*(-4)^2\)

\(u_{n}=3*(-4)^{n-1}\)


Answer: \(a_n=3(-4)^{n-1}\)

Step-by-step explanation:

Given sequence : \(3, -12, 48, -192, ...\)

Here, First term \(a_1=3\)

Second term \(a_2=-12\)

and  Ratio=\(r=\frac{a_2}{a_1}=\frac{-12}{3}=-4\)

Third term \(a_3=48\)

Ratio=\(r=\frac{a_3}{a_2}=\frac{48}{-12}=-4\)

Fourth term \(a_4=-192\)

Ratio=\(r=\frac{a_4}{a_3}=\frac{-192}{48}=-4\)

Thus, the given sequence is geometric sequence with the common ratio r = -4.

The explicit rule for for the nth term in geometric sequence is given by

\(a_n=a_{1}r^{n-1}\)

Then the explicit rule for the nth term of the given sequence will be :-

\(a_n=3(-4)^{n-1}\)