Use the summation formula to find a partial sum of a series with the following properties
Geometric
a1= -11
a7= -45,056
n= 7
r= -4

Respuesta :

Answer:

-36,047.

Step-by-step explanation:

Sum of n terms =  a1 .( r^n - 1) / (r - 1)

So Sum of 7 terms =  -11 . ((-4)^7 - 1 / (-4-1)

= -11 *  -16,385 / -5

= -36,047.