Find the sum S of the infinite series Σk=1∞ 5·(1/2)ᵏ.
Sequences & series worksheet with answers
1.Easy
a = 5r = 1/2k₀ = 1
S =
2.Easy
Find the sum S5 of the first 5 terms of the geometric sequence 3, 6, 12, …
a₁ = 3r = 2n = 5
S5 =
3.Medium
Exactly one of the four series converges. Click it.
A: Σ 1/(k(k + 2))B: Σ (5/3)ᵏC: Σ 1/√kD: Σ ln k / k
- 1A: Σ 1/(k(k + 2))
- 2B: Σ (5/3)ᵏ
- 3C: Σ 1/√k
- 4D: Σ ln k / k
4.Medium
Find the sum S = Σk=140 6/(k(k + 1)).
ak = 6/(k(k + 1))n = 40
S =
5.Hard
Recognise the series and find its sum: S = Σk=1∞ k·(1/3)ᵏ.
ak = k·(1/3)ᵏ
S =
6.Hard
Find the coefficient c₃ of (x + 1)³ in the Taylor series of f(x) = e2x about a = −1.
f(x) = e2xa = −1k = 3
c₃ =
Answer key
- 1. S = 5
- 2. S5 = 93
- 3. A: Σ 1/(k(k + 2))
- 4. S = 5.854
- 5. S = 0.75
- 6. c₃ = 0.1804
Full step-by-step solutions: practise this topic on examproblems.com.