tentuakn deret S1,S2,S3 dan S4 dari deret di bawah ini:b.2+(-4)+8+(-16)+..

a = 2
r = -4/2 = -2
Sn = a(1 - r^n) / (1 - r)
S1 = 2(1 - (-2)^1) / (1 - (-2))
S1 = 2(1 - (-2)) / 3
S1 = 2(3) / 3
S1 = 6/3
S1 = 2

S2 = 2(1 - (-2)^2) / (1 - (-2))
S2 = 2(1 - 4) / 3
S2 = 2(-3) / 3
S2 = -6/3
S2 = -2

S3 = 2(1- (-2)^3) / (1 - (-2))
S3 = 2(1 - (-8)) / 3
S3 = 2(9) / 3
S3 = 18/3
S3 = 6

S4 = 2(1 - (-2)^4) / (1 - (-2))
S4 = 2(1 - 16) / 3
S4 =2(-15) / 3
S4 = -30/3
S4 = -10