Question

Carilah jumlah 10 suku pertama dari deret geometri 256+128+64+32+...

Answer 1

A = 256
r = 128/256 = 0,5

S10 = a (1 -r^10) / (1-r)
     = 256 (1- (1/2)^10) /(1-1/2)
    = 256 ( 1-  1/1.024) / 1/2
    = 512 ( 1.024/1.024 - 1/1.024)
  = 512 ( 1.023 / 1.024)
   = 1023 / 2
 =  511, 5

Answer 2