If a1 = 4 and an = -2an-1 then find the value of a6.

2048

Step-by-step explanation:

Time to use recursive formula :)

Since a of 1 = 4 and -the recursive formula is

-2(a of n-1) We know that the r = -2

Convert that to explicit is

f(n) = -2 * 4^n-1

Let's use that to get  the value for a of 6.

f(6) = -2 * 4^6-1

= -2 * 4^5

= -2048