Question

calcule o 15° termo da pg(256,128,64,...)

Answer 1

a1 = 256
a2 = 128
a3 = 64

q = 128/256 = 1/2 ***

a15 = a1q¹⁴  = 256 * ( 1/2)¹⁴ =  256 *  ( 1/16384)  =  256/16384 =1/64 ***

Answer 2

PG(256,128,64,...)

q=128/256
q=1/2
an = a1.q^n-1
a15 = 256*(1/2)^15-1
a15= 256*(1/2)^14
a15 = 256*1/16384
a15 = 1/64