Periodic tableThe periodic table, also known as the periodic table of the elements, arranges the chemical elements into rows ("periods") and columns ("groups"). It is an organizing icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which says that when the elements are arranged in order of their atomic numbers an approximate recurrence of their properties is evident. The table is divided into four roughly rectangular areas called blocks.
ContradictionIn traditional logic, a contradiction occurs when a proposition conflicts either with itself or established fact. It is often used as a tool to detect disingenuous beliefs and bias. Illustrating a general tendency in applied logic, Aristotle's law of noncontradiction states that "It is impossible that the same thing can at the same time both belong and not belong to the same object and in the same respect.
Law of noncontradictionIn logic, the law of non-contradiction (LNC) (also known as the law of contradiction, principle of non-contradiction (PNC), or the principle of contradiction) states that contradictory propositions cannot both be true in the same sense at the same time, e. g. the two propositions "p is the case" and "p is not the case" are mutually exclusive. Formally, this is expressed as the tautology ¬(p ∧ ¬p). The law is not to be confused with the law of excluded middle which states that at least one, "p is the case" or "p is not the case" holds.
IranIran, also known as Persia and officially as the Islamic Republic of Iran, is a country located in West Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmenistan to the north, by Afghanistan and Pakistan to the east, and by the Gulf of Oman and the Persian Gulf to the south. It covers an area of , making it the 17th-largest country. With an estimated population of 86.8 million, Iran is the 17th-most populous country, and the second largest in the Middle East.
Party of the Democratic RevolutionThe Party of the Democratic Revolution (PRD, Partido de la Revolución Democrática, paɾˈtiðo ðe la reβoluˈsjon demoˈkɾatika) is a social democratic political party in Mexico. The PRD originated from the Democratic Current, a political faction formed in 1986 from the Institutional Revolutionary Party (PRI). The PRD was formed after the contested general election in 1988, which the PRD's immediate predecessor, the National Democratic Front, believed was rigged by the PRI. This sparked a movement away from the PRI's authoritarian rule.
MexicoMexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatemala, Belize, and the Caribbean Sea; and to the east by the Gulf of Mexico. Mexico covers 1,972,550 km2 (761,610 sq mi), making it the world's 13th-largest country by area; with a population of over 126 million, it is the 10th-most-populous country and has the most Spanish speakers.
PakistanPakistan ( ˈpaːkɪstaːn), officially the Islamic Republic of Pakistan (ISO: , islāmi jamhūriyāh pākistān), is a country in South Asia. It is the world's fifth-most populous country, with a population of 241.5 million people, and has the world's largest Muslim population as of year 2023. Islamabad is the nation's capital, while Karachi is its largest city and financial centre, followed by Lahore and Faisalabad. Pakistan is the 33rd-largest country in the world by area and the second-largest in South Asia, spanning .
Euler–Lagrange equationIn the calculus of variations and classical mechanics, the Euler–Lagrange equations are a system of second-order ordinary differential equations whose solutions are stationary points of the given action functional. The equations were discovered in the 1750s by Swiss mathematician Leonhard Euler and Italian mathematician Joseph-Louis Lagrange. Because a differentiable functional is stationary at its local extrema, the Euler–Lagrange equation is useful for solving optimization problems in which, given some functional, one seeks the function minimizing or maximizing it.
Lagrangian mechanicsIn physics, Lagrangian mechanics is a formulation of classical mechanics founded on the stationary-action principle (also known as the principle of least action). It was introduced by the Italian-French mathematician and astronomer Joseph-Louis Lagrange in his 1788 work, Mécanique analytique. Lagrangian mechanics describes a mechanical system as a pair consisting of a configuration space and a smooth function within that space called a Lagrangian. For many systems, where and are the kinetic and potential energy of the system, respectively.