diketahui barisan geometri 1/2, 1/3, 2/9,... 32/729. jika un = 32/729 nilai n yang memenuhi... a.9 c.7 e.5 b.8 d.6
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diketahui barisan geometri 1/2, 1/3, 2/9,... 32/729. jika un = 32/729 nilai n yang memenuhi...
a.9 c.7 e.5
b.8 d.6
a.9 c.7 e.5
b.8 d.6
2 Jawaban
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1. Jawaban MuhammmadRizky
Barisan dan Deret
Matematika
Kelas X SMA
Kurikulum 2013
a = 1/2
r = 1/3 x 2/1
r = 2/3
Un ⇒ 1/2 x (2/3)^n - 1 = 32/729
(2/3)^n - 1 = 64/729
n - 1 . log (2/3) = log (64/729)
n - 1 = log (64/729)/log (2/3)
n - 1 = 6
n = 7 (C)
Semoga Membantu!!!
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2. Jawaban LupaPakeCelanaDalam
Un = ar^(n-1)= 1/2. 2/3^(n-1) = 32/729
(2/3)^(n-1) = 64/729
(2/3)^(n-1)= (2/3)^6
maka n-1= 6
n = 6 + 1
n = 7