Diketahui barisan geometri dengan suku ke 4 = 15 suku ke 5 = 5 a. hitung rasionya b. tentukan U c. tentukan suku ke 8 d. hitung suku ke 8
NB: mohon bantuannya kak sebisanya aja!
5dregensleyerjawaban soa a U5 → a x r⁴ = 5 U4 → a x r³ = 15 _ r = 1/3 jawaban soal b persamaan a x r³ = 15 a x 1/3³ = 15 a x 1/27 = 15 a = 15 : 1/27 a = 15 x 27 = 405 u1 = a = 405 jawaban soal C u8 = a x r^n-1 = 405 x (1/3)^(8-1) = 405 x (1/3)^7 = 405 x 1/2187 = 405/2187 = 5/27 jawaban soal D ------ maaf ------ gak tuntas jwbnya -----
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Takamori37
Segmen antar pilihan jawaban terpisah di lampiran-lampiran berikut:
U5 → a x r⁴ = 5
U4 → a x r³ = 15 _
r = 1/3
jawaban soal b
persamaan
a x r³ = 15
a x 1/3³ = 15
a x 1/27 = 15
a = 15 : 1/27
a = 15 x 27
= 405
u1 = a = 405
jawaban soal C
u8 = a x r^n-1
= 405 x (1/3)^(8-1)
= 405 x (1/3)^7
= 405 x 1/2187
= 405/2187
= 5/27
jawaban soal D
------ maaf ------ gak tuntas jwbnya -----