tolong ya kk. terima kasih

Kelas 8 Matematika
Bab Barisan dan Deret Bilangan

^ = pangkat

r = ^(4 - 1)√(U4 / U1)
r = ∛(48/6)
r = ∛8
r = 2

Sn = a . (rⁿ - 1) / (r - 1)
S6 = 6 . (2⁶ - 1) / (2 - 1)
S6 = 6 . (64 - 1) / 1
S6 = 6 . 63
S6 = 378