Respuesta :

Answer:

a1=7

an = an-1 * -2

Step-by-step explanation:

7,-14,28,-56

The first term is a1 so a1 = 7

We are multiply by -2 each time

7*-2 =-14

-14*-2 =28

28*-2 = -56

an = a(n-1) * -2