Question

Use the iterative rule to find the 5th term in the sequence:

an = 4x3n-1
972
243
324
81

Answer 1

5th term = 324

Explanation:

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

Where, n = 5

`a_5 \: = \: 4 \: \cdot \: {3}^(5 - 1)`

`a_5 \: = 4 \: \cdot \: {3}^(4)`

`a_5 \: = 4 \: \cdot \: 81`

`a_5 \: = \: 324`

Answer 2

324

Explanation:

1) substitute the 5 into the formula

n=5
`a_(n)=4`×
`3^(5-1)`

2) simplify

5-1 = 4

`3^4` = 81

4×81 = 324

Hope this helps, have a great day!