Diketahui deret grometro dengan suku kedua 16 dan suku ketujuh 1/64. suku ke 4 adalah…
Jawaban Terkonfirmasi
Mapel : Matematika
Bab : Barisan dan Deret Geometri
Un = ar^n-1
U2 = ar^2-1
16 = ar
Un = ar^n-1
U7 = ar^7-1
1/64 = ar^6
ar^6 / ar = 1/64 / 16
r^5 = 1/64 x 1/16
r^5 = 1/1024
r = 1/4
16 = ar
16 = a x 1/4
a = 16 x 4/1
a = 64
Un = ar^n-1
U4 = 64 x (1/4)^4-1
U4 = 64 x (1/4)^3
U4 = 64 x 1/64
U4 = 1
U2 -> a.r = 16
u7 -> a.r6 = 1/64
a = 16/r
(16/r).r6 = 1/64
16r5 = 1/64
r5 = 1/1024
r = 1/4
a.1/4 = 16
a = 64
u4 = 64.1/64 = 1