Saya butuh jwb 4,30,dan,28
Jawaban:
28.
Diketahui U¹ = a = 25 dan U⁴= ar⁴ = 200
u⁴ = 200
ar³ = 200
25 x r³ = 200
r³= 8
r³ = ³√8
r³= 2
Sn = a(rn-1) / r-1
S⁴ = 25(2⁴-1) / 2-1
S⁴ =25(16-1)
S⁴ = 25 x15
S⁴ = 375
jadi jawaban 375 cm
30.
aritmatika
105, 112, 119, …., 196
a = 105
b = 7
Un = a + (n – 1) 7 = 196
105 + (n – 1) 7 = 196
(n – 1) 7 = 196 – 105
n – 1 = 91/7
n = 13 + 1
n = 14
Sn = n/2 x (a + Un)
S14 = 14/2 x (105 + 196)
S14 = 7 x 301
S14 = 2.107
jawaban A.2.107
terima kasih, jgn lupa follow