The Picone identity is a useful result in the theory of differential equations, particularly for second-order linear ordinary differential equations. It provides a way to relate two solutions of a second-order linear differential equation, allowing one to derive properties about solutions based on their behavior.
Pfister's sixteen-square identity is a fascinating result in the study of quadratic forms in algebra. It states that the range of a quadratic form that represents a certain class of integers can be expressed as a combination of simpler quadratic forms.
Noether identities are a set of relations that arise in the context of Lagrangian field theories, particularly in relation to symmetries and conservation laws as formulated by the mathematician Emmy Noether. These identities are closely tied to Noether's theorem, which states that every continuous symmetry of the action of a physical system corresponds to a conservation law. Noether identities typically arise when dealing with gauge theories or systems with constraints and play an important role in ensuring the consistency of the theory.
Morrie's Law, often attributed to Morrie Schwartz, a sociology professor who became widely known through the book "Tuesdays with Morrie" by Mitch Albom, suggests that the more one embraces suffering and life’s challenges, the more wisdom, strength, and insight one can gain. The essence of Morrie's teachings emphasizes the importance of human connection, the inevitability of death, and the pursuit of meaningful relationships.
The Mingarelli identity is a mathematical identity that is often used in the context of number theory and combinatorial mathematics. It is related to partitions of numbers and can be expressed in various ways, typically involving sums over specific sets or sequences. However, as of my last update in October 2023, detailed information specifically about the Mingarelli identity isn't readily available in standard reference materials or mathematical literature. It may not be as widely recognized or documented as other mathematical identities.
The Maximum-Minimum Identity is a mathematical principle often associated with calculus and optimization problems, specifically in the context of functions and their extrema. Although it might not have a universally recognized name, the concept generally relates to the relationship between the maximum and minimum values of a function over a certain domain.
Macdonald identities are a set of identities in the theory of symmetric functions, named after I.G. Macdonald. These identities relate certain algebraic structures known as symmetric functions, particularly the Macdonald polynomials, to various combinatorial objects. The identities typically express symmetric polynomials, which can be thought of as generating functions for certain combinatorial objects, in terms of other symmetric polynomials.
Lists of integrals typically refer to collections or tables that provide the integrals of various functions, which can be useful for students and mathematicians when solving calculus problems. These lists usually include both definite and indefinite integrals, covering a wide range of functions, including polynomial, trigonometric, exponential, logarithmic, and special functions. The format of a list of integrals will often present the integral alongside its result, often accompanied by conditions related to the variables in the integrals.
Trigonometric identities are equations involving trigonometric functions that are true for all values of the variables involved, provided the functions are defined. Here’s a list of some of the most important trigonometric identities: ### Fundamental Identities 1.
In set theory, identities and relations help define how sets interact with one another. Here’s a list of some key set identities and relations: ### Set Identities 1. **Idempotent Laws** - \( A \cup A = A \) - \( A \cap A = A \) 2.
A list of mathematical identities consists of equations that hold true for all values of the involved variables, assuming the variables are within the defined domain of the identity. Below, I provide a selection of important mathematical identities across different branches of mathematics: ### Algebraic Identities 1. **Difference of Squares**: \[ a^2 - b^2 = (a - b)(a + b) \] 2.
Logarithmic identities are mathematical properties that describe the relationships between logarithms. Here are some of the most common logarithmic identities: 1. **Product Identity**: \[ \log_b(MN) = \log_b(M) + \log_b(N) \] The logarithm of a product is the sum of the logarithms.
Liouville's formula is a significant result in the theory of differential equations, particularly in the context of linear ordinary differential equations. It describes the behavior of the Wronskian determinant of a system of linear ordinary differential equations.
The Lerche–Newberger sum rule is a principle in the field of statistical mechanics and thermodynamics, related to the behavior of systems in equilibrium. Specifically, it provides a relationship between correlation functions and the equilibrium properties of a system, particularly in contexts where random variables influence outcomes. The rule states that the sum of certain statistical correlators (usually related to physical observables) over all possible states of a system leads to significant simplifications.
Lagrange's identity is a mathematical concept often associated with boundary value problems and involves functions defined in a certain domain with specific conditions. It is frequently used in the context of differential equations, particularly in relation to the solutions of second-order linear differential equations. In its classical form, Lagrange's identity relates solutions of a differential equation to their Wronskian, which is a determinant used to analyze the linear independence of a set of functions.
The Jacobi–Anger expansion is a mathematical identity that expresses the exponential function of a complex argument in terms of Bessel functions of the first kind. Specifically, it characterizes the relationship between the exponential function and the Bessel functions when the argument of the exponential function is a complex variable.
The Jacobi triple product is an important identity in the theory of partitions and combinatorial mathematics. It relates the series expansion of certain infinite products and has applications in number theory, combinatorics, and the study of special functions.
The Jacobi identity is a fundamental relation in the theory of Lie algebras and differentiable manifolds, particularly in the context of the Lie brackets and Poisson brackets. It characterizes the behavior of the algebraic structures defined by these brackets.
Integration by parts is a technique used in calculus to integrate the product of two functions. It's based on the product rule for differentiation and is particularly useful when dealing with integrals of the form \( \int u \, dv \), where \( u \) and \( dv \) are functions that we can choose strategically to simplify the integration process.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact