Formula generala:
bn=(bn_1)×q
26.
A. b1=6, q=2
b1=6;b2=12;b3=24;b4=48;b5=96
B. b1=-10; q=1/2
b1=-10;b2=-5;b3=-5/2;b4=-5/4;
b5=-5/8
C. b1=-24;q=-0,5=-1/2
b1=-24;b2=12;b3=-6;b4=3;b5=-3/2
D. b2=0,5=1/2;q=rad (3)
b1=1/(2×rad (3));b2=1/2;b3=rad (3)/2;
b4=3/2;b5=3×rad (3)/2
27.
A. y1, y2, 24, 36, 54, ..
q=36/24=3/2
y2=24×2/3=48/3=16
Y1=16×2/3=32/3
B. y1, y2, 225, -135, 81, ..
q=-135/225=-3/5
y2=-225×5/3=-375
y1=375×5/3=625