Բանաձև՝

Sn = b₁(1 — qⁿ)/1 — q — ընդհանուր
S_∞ = b₁/1 — q

Առաջադրանքներ`

S_∞ = 2/1 — q
q = b₂/b₁ = 1/2 = 0,5
S_∞ = 2/1 — 0,5 = 4

S_∞ = 3/1 — q
q = b₂/b₁ = 1/3
S_∞ = 3/1 — 1/3 = 3/2/3 = 9/2

S_∞ = 4/1 — q
q = b₂/b₁ = 1/4 = 0,25
S_∞ = 4/1 — 0,25 = 5,ɑ

S_∞ = 5/1 — q
q = b₂/b₁ = 1/5 = 0,2
S_∞ = 5/1 — 0,2 = 6,25

S_∞ = 6/1 — q
q = b₂/b₁ = 1/6
S_∞ = 6/1 — 1/6 = 6/5/6 = 36/5

q = b₃/b₂ = 16/8 = 2
b₂ = b¹ * q
8 = b₁ * 2
8/2 = b₁
b₁ = 4

q = b₃/b₂ = 9/3 = 3
b₂ = b¹ * q
3 = b¹ * 3
3/3 = b₁
b₁ = 1

q = b₃/b₂ = 8/4 = 2
b₂ = b¹ * q
4 = b¹ * 2
4/2 = b¹
2 = b¹

q = b₃/b₂ = 15/5 = 3
b₂ = b¹ * q
5= b¹ * 3
5/3 = b¹

q = b₃/b₂ = 18/6 = 3
b₂ = b¹ * q
6 = b₁ * 3
6/3 = b₁
b₁ = 2

b₁ * 10 = 80