What is the 6th term in the sequence described by the following recursive formula?

a1=9
an=an−1−4

a) a6=−7
b) a6=−15
c) a6=−8
d) a6=−11

Correct answer is: D) a₆ = - 11

Step-by-step explanation:

Given:

a₁ = 9 and aₙ = aₙ₋₁ - 4

We know it is

a₆ = a₅ + d also it is given a₆ = a₅ - 4

When we equate the right sides of equality we get:

a₅ + d = a₅ - 4 => d = - 4

We also know it is   a₆ = a₁ + 5 d

Now we will find a₆

a₆ = 9 + 5 (-4) = 9 - 20 = - 11

a₆ = - 11

God with you!!!