Question

calcule a soma da P.G. (4,2,...)

Answer 1

a1 = 4
a2 = 2
q = 2/4 = 1/2 ****
Sn = a1 / ( 1 - q )
Sn =  4/ ( 1/1 - 1/2)  = 4/(1/2) = 4/1 : 1/2  = 4/1 * 2/1 = 8 ****