Question

encontre a soma dos termos da P.G. (3/4,-1/2,1/3,-1,9,...)

Answer 1

a1 = 3/4
q = a2/a1
q = (-1/2)/(3/4)
q = (-1/2).(4/3)
q = -4/6 
q = -2/3
Sn = a1/(1-q)
Sn = (3/4)/(1-(-2/3))
Sn = (3/4)/(1+2/3)
Sn = (3/4)/(3/3+2/3)
Sn = (3/4)/(5/3)
Sn = (3/4).(3/5)
Sn = 9/20