Question

If a1=9 and an = -3an-1 what is a5

Answer 1

`So, \(a_5 = 729\).`

Explanation:

To find the value of \(a_5\) in the sequence where \(a_1 = 9\) and \(a_n = -3a_{n-1}\), you can use the recursive definition to calculate each term. Let's find \(a_5\):

`\(a_2 = -3a_1 = -3(9) = -27\)`

`\(a_3 = -3a_2 = -3(-27) = 81\)`

`\(a_4 = -3a_3 = -3(81) = -243\)`

`\(a_5 = -3a_4 = -3(-243) = 729\)`

`So, \(a_5 = 729\).`