If 3,x,y,18,... are in a geometric progression find x and y
X=4
Y=5
3×4=12, 3x5=15, 3x6=18
r^3 = 18/3 = 6
r = ∛6
so the terms are
3, 3∛6, 3∛36, 18
unusual, but if it's an AP, then d=5 and you have
3,8,13,18
Y=5
3×4=12, 3x5=15, 3x6=18
r = ∛6
so the terms are
3, 3∛6, 3∛36, 18
unusual, but if it's an AP, then d=5 and you have
3,8,13,18