Background image of landing

Unrivalled
Education
Solutions for your
Family

Determine the sum of an infinite harmonic series

The sum of an infinite harmonic series diverges to infinity.

An infinite harmonic series is defined as follows:

1+12+13+14+1 + \frac{1}{2} + \frac{1}{3} + \frac{1}{4} + \ldots

To investigate whether this series converges or diverges, we can utilize the harmonic series test. This test asserts that if the terms of a series are structured as 1n\frac{1}{n}, where nn is a positive integer, then the series diverges.

To understand why this is true, we can apply the integral test. This test states that if f(x)f(x) is a positive, decreasing function, then the series f(n)\sum f(n) converges if and only if the integral f(x)dx\int f(x) \, dx converges.

For the harmonic series, we can define the function:

f(x)=1xf(x) = \frac{1}{x}

This function is both positive and decreasing for x>0x > 0, allowing us to apply the integral test. Evaluating the integral, we have:

1xdx=ln(x)+C\int \frac{1}{x} \, dx = \ln(x) + C

As xx approaches infinity, ln(x)\ln(x) diverges, indicating that the integral diverges. Consequently, the series also diverges. Thus, we conclude that the sum of the infinite harmonic series diverges to infinity.

In simpler terms, the sum of the series:

1+12+13+14+1 + \frac{1}{2} + \frac{1}{3} + \frac{1}{4} + \ldots

is infinite. This implies that no matter how many terms we add together, the total will continue to grow larger and larger without bound.

Answered by: Prof. Peter Brown
IB Maths Tutor
Medal Icon

100%

Globe Icon

Global

Crest Icon

97%

Professional Tutors

International Tuition

Independent School Entrance Success

All of our elite tutors are full-time professionals, with at least five years of tuition experience and over 5000 accrued teaching hours in their subject.

Based in Cambridge, with operations spanning the globe, we can provide our services to support your family anywhere.

Our families consistently gain offers from at least one of their target schools, including Eton, Harrow, Wellington and Wycombe Abbey.

Medal Icon

100%

Professional Tutors

All of our elite tutors are full-time professionals, with at least five years of tuition experience and over 5000 accrued teaching hours in their subject.

Globe Icon

Global

International Tuition

Based in Cambridge, with operations spanning the globe, we can provide our services to support your family anywhere.

Crest Icon

97%

Independent School Entrance Success

Our families consistently gain offers from at least one of their target schools, including Eton, Harrow, Wellington and Wycombe Abbey.

Book a free
30-minute consultation
session

At the Beyond Tutors we recognise that no two students are the same. 

That’s why we’ve transcended the traditional online tutoring model of cookie-cutter solutions to intricate educational problems. Instead, we devise a bespoke tutoring plan for each individual student, to support you on your path to academic success.

To help us understand your unique educational needs, we provide a free 30-minute consultation with one of our founding partners, so we can devise the tutoring plan that’s right for you.

To ensure we can best prepare for this consultation, we ask you to fill out the short form below.

Hire a Tutor

All the form fields are optional, but we ask you to provide as much information as possible so that we are in a better position to quickly meet your tutoring requirements.

Still have questions?
Let's get in touch