# 41 Lecture

## Sequence

Sequence is a fundamental concept in mathematics, particularly in calculus and analytical geometry. It is a set of numbers that follow a specific pattern or rule.

## Important Mcq's Midterm & Finalterm Prepration Past papers included

Which of the following is a recursive formula for the Fibonacci sequence?

a) f_n = n^2

b) f_1 = 1, f_2 = 1, f_n = f_{n-1} + f_{n-2}

c) f_n = n!

d) f_n = 2^n

Answer: b) f_1 = 1, f_2 = 1, f_n = f_{n-1} + f_{n-2}

What is the nth term of the arithmetic sequence 2, 5, 8, 11, ...?

a) 2n + 1

b) 3n + 1

c) 3n - 1

d) 2n + 2

Which of the following tests is used to determine whether an infinite series converges or diverges?

a) Comparison test

b) Limit comparison test

c) Integral test

d) All of the above

Answer: d) All of the above

What is the sum of the geometric series 1/2 + 1/4 + 1/8 + ... + (1/2)^n + ...?

a) 1

b) 2

c) 3/2

d) 4/3

Which of the following is a bounded sequence?

a) {n^2}

b) {(-1)^n}

c) {1/n}

d) {n/(n+1)}

Which of the following is an example of an arithmetic sequence?

a) 1, 3, 9, 27, ...

b) 1, 2, 4, 8, ...

c) 2, 4, 8, 16, ...

d) 1, 1/2, 1/4, 1/8, ...

Answer: b) 1, 2, 4, 8, ...

What is the nth term of the geometric sequence 1, 2, 4, 8, ...?

a) 2^n

b) 2n

c) n^2

d) n!

Which of the following is an example of a divergent series?

a) 1/2 + 1/4 + 1/8 + ... + (1/2)^n + ...

b) 1 + 1/2 + 1/3 + ... + 1/n + ...

c) 1 - 1/2 + 1/3 - ... + (-1)^n/n + ...

d) e^x = 1 + x + x^2/2! + x^3/3! + ...

Answer: c) 1 - 1/2 + 1/3 - ... + (-1)^n/n + ...

What is the limit of the sequence {1/n} as n approaches infinity?

a) 0

b) 1

c) -1

d) Does not exist

Which of the following is a formula for the nth term of a geometric sequence?

a) a_n = a_1 + (n-1)d

b) a_n = a_1*r^(n-1)

c) a_n = n^2

d) a_n = a_1 + r^n

## Subjective Short Notes Midterm & Finalterm Prepration Past papers included

What is a sequence?

A sequence is a list of numbers arranged in a specific order that follows a pattern or rule.

How can a sequence be defined?

A sequence can be defined through a formula or a recursive formula.

What is the difference between a bounded and an unbounded sequence?

A bounded sequence is limited between two specific values, while an unbounded sequence has no limit.

What is the Fibonacci sequence?

The Fibonacci sequence is a famous sequence defined recursively by the formulas f_1 = 1, f_2 = 1, and f_n = f_{n-1} + f_{n-2} for n ? 3.

What is the squeeze theorem?

The squeeze theorem is a technique used to approximate the value of a limit of a function using a sequence that converges to the limit.

What is a series?

A series is the sum of the terms of a sequence, which can be either finite or infinite.

What is the difference between a convergent and a divergent series?

A series is convergent if the sum of the terms approaches a finite limit as the number of terms increases to infinity, while a series is divergent if the sum of the terms does not approach a finite limit.

What are some tests for determining whether a series is convergent or divergent?

Some tests for determining whether a series is convergent or divergent include the comparison test, the ratio test, and the integral test.

How can sequences be used in calculus?

Sequences can be used to approximate the value of a limit of a function and to determine the convergence or divergence of a series.

Can a sequence be defined in other ways besides a formula or a recursive formula?

Yes, a sequence can also be defined using a table or a graph of its values.

Sequence is a fundamental concept in mathematics, particularly in calculus and analytical geometry. It is a set of numbers that follow a specific pattern or rule. In other words, it is a list of numbers arranged in a specific order. Sequences are commonly used to study the behavior of functions, series, and limits.

### What is Sequences?

A sequence can be defined in several ways, but the most common way is through a formula. The formula defines a relationship between each term and the one that precedes it. For example, the sequence 1, 3, 5, 7, 9, ... can be defined by the formula a_n = 2n - 1, where a_n represents the nth term of the sequence. Another way to define a sequence is through a recursive formula. In this case, each term is defined in terms of the previous one. For example, the Fibonacci sequence, which is widely known, can be defined recursively by the formulas f_1 = 1, f_2 = 1, and f_n = f_{n-1} + f_{n-2} for n ? 3. Sequences can be classified into two types: bounded and unbounded. A bounded sequence is one that is limited between two specific values, while an unbounded sequence is one that has no limit. For example, the sequence 1, -1, 1, -1, ... is bounded between -1 and 1, while the sequence 1, 2, 3, 4, ... is unbounded. Sequences are useful in calculus for studying the behavior of functions. For example, a sequence can be used to approximate the value of a limit of a function. If the sequence converges to a specific value, then that value can be considered as the limit of the function. This technique is commonly known as the squeeze theorem. Another important application of sequences is in series. A series is the sum of the terms of a sequence, and it can be either finite or infinite. If the series is infinite, then it can be convergent or divergent. A series is said to be convergent if the sum of the terms approaches a finite limit as the number of terms increases to infinity. A series is said to be divergent if the sum of the terms does not approach a finite limit. There are several tests for determining whether a series is convergent or divergent, including the comparison test, the ratio test, and the integral test. These tests involve using the properties of sequences and limits to determine the behavior of the series. In conclusion, sequences are a fundamental concept in calculus and analytical geometry. They are used to study the behavior of functions, series, and limits. Sequences can be defined through a formula or a recursive formula, and they can be classified as bounded or unbounded. Sequences are useful for approximating the value of a limit of a function and for determining the convergence or divergence of a series.