Question

Find the 8th term of the geometric sequence whose common ratio is 2/3 and whose first term is 7​

Answer 1

Answer:

The 8th term of the sequence is 896/2187.

Step-by-step explanation:

We want to find the 8th term of a geometric sequence whose common ratio is 2/3 and whose first term is 7.

We can write a direct formula. Recall that the direct formula of a geometric sequence is given by:

$\displaystyle x_{n} = a\left(r\right)^{n-1}$

Where a is the initial term and r is the common ratio.

Substitute:

$\displaystyle x_{n} = 7\left(\frac{2}{3}\right)^{n-1}$

To find the 8th term, let n = 8. Substitute and evaluate:

$\displaystyle \begin{aligned} x_{8} &= 7\left(\frac{2}{3}\right)^{(8) - 1} \\ \\ &= 7\left(\frac{2}{3}\right)^{7} \\ \\ &= 7\left(\frac{128}{2187}\right) \\ \\ &= \frac{896}{2187} = 0.4096...\end{aligned}$

In conclusion, the 8th term of the sequence is 896/2187.