Sequences

Recursively defined sequences

Types of exercises: terms of a recursively defined sequence, a recursive formula for the given terms, sum of the first terms of a recursively defined sequence.

Exercises are drawn at random from a large bank - every click gives a different set.

Solved: 0 of 10

1

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the given sum of its first terms

a₁ = −4, aₙ₊₁ = −aₙ + 1, a₁ + a₂ + a₃ + a₄ = ?

2

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the indicated term

a₁ = 7, aₙ₊₁ = −2aₙ − 5, a₄ = ?

3

The sequence (aₙ) is defined recursively for n ≥ 1 and its first terms are given below. Which formula describes this sequence?

2, 3, 4, 5, …

4

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the given sum of its first terms

a₁ = −1, aₙ₊₁ = −3aₙ − 5, a₁ + a₂ + a₃ + a₄ = ?

5

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the indicated term

a₁ = 2, aₙ₊₁ = aₙ − 2n, a₃ = ?

6

The sequence (aₙ) is defined recursively for n ≥ 1 and its first terms are given below. Which formula describes this sequence?

0, −3, −12, −39, …

7

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the given sum of its first terms

a₁ = 2, aₙ₊₁ = aₙ + 4, a₁ + a₂ + a₃ + a₄ + a₅ = ?

8

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the indicated term

a₁ = 2, aₙ₊₁ = −aₙ + 2, a₄ = ?

9

The sequence (aₙ) is defined recursively for n ≥ 1 and its first terms are given below. Which formula describes this sequence?

−4, −1, −4, −1, …

10

The sequence (aₙ) is defined recursively for n ≥ 1. Compute the given sum of its first terms

a₁ = −7, aₙ₊₁ = aₙ + n − 3, a₁ + a₂ + a₃ + a₄ + a₅ = ?

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Recursively defined sequences - exercises with solutions (Sequences) | PhiBoard