Question

Tentukan banyak suku pada barisan geometri 3,-6,12,....,768

Answer 1

Un = ar^n-1 768 = 3 x (-2 )^n-1 768/3 = (-2)^n-1 256 = (-2)^n-1 (-2)^8 = (-2)^n-1 8 = n-1 7 = n

Answer 2

3,6,12,...,768
a=3
r=2

Un=ar^(n-1)
768=3.2^(n-1)
2^(n-1)=768/3
2^(n-1)=256
2^(n-1)=2^8
n-1=8
n=8+1
n=9