Question

What are the geometric series of a1 and r of the geometric series? 2-2+2-2+2

Answer 1

Answer:

a1=2 and r=-1

Step-by-step explanation:

Given

geometric series= 2-2+2-2+2

geometric sequence has a constant ratior r and is given by

an=a1r(r)^(n-1)

where

an=nth term

r=common ratio

n=number of term

a1=first term

In given series:

r= a(n+1)/an

 = a(2)/a1

 = -2/2

  =-1

so a1=2 and r=-1 !