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Today's featured article

Example of a polynomial equation, studied in elementary algebra

Algebra is the branch of mathematics that studies certain abstract systems, known as algebraic structures, and the manipulation of statements within these systems. Elementary algebra generalizes arithmetic by using variables in addition to numbers. It covers methods of transforming equations to solve them by isolating variables. Linear algebra examines systems of several linear equations and techniques to determine for which values all equations in a system are true at the same time. Abstract algebra investigates algebraic structures, which consist of a set of objects together with operations defined on that set. It distinguishes algebraic structures, such as groups, rings, and fields, based on their number of operations and the laws they follow. Algebraic methods were first studied in ancient times to solve specific problems. As algebra evolved, it became increasingly abstract and generalized, leading to many applications in other branches of mathematics and the empirical sciences. (Full article...)

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In the news

Bashar al-Assad

Syrian rebel forces capture Damascus following multiple offensives as overthrown president Bashar al-Assad (pictured) flees to Russia.
Notre-Dame de Paris reopens following reconstruction after the 2019 fire.
The first round of the Romanian presidential election is annulled by the Constitutional Court following allegations of Russian electoral interference.
The French government, led by Michel Barnier, collapses following a vote of no confidence by the National Assembly.

Today's featured picture

Marcelo Rebelo de Sousa (born 12 December 1948) is a Portuguese politician and academic. He has been the 20th and current president of Portugal since 9 March 2016. As a member of the Social Democratic Party, he previously served as a minister and parliamentarian in the Assembly of the Republic. This photograph of Rebelo de Sousa was taken in 2017 at Web Summit, an annual technology conference held in Lisbon.

Photograph credit: João Pedro Correia

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Did you know...

Carlyle Hotel

... that a staff member at the Carlyle Hotel (pictured) once lent his own bow tie to Laurence Olivier?
... that Yangginu plotted to defeat Khan Wan to avenge his murdered father?
... that to prepare for her role in The Last Dance, actress Michelle Wai learned to perform a Taoist funeral ritual traditionally performed only by men?
... that the city council of Hamtramck, led by Mayor Amer Ghalib, banned the pride flag from publicly owned flagpoles?
... that the death rate from adrenal crises can reach as high as 6 percent?
... that Shane Connolly has provided flowers for two royal weddings and the coronation of Charles III?
... that the Child Law Project reports on Ireland's child care system?
... that U.S. Army chaplain Patrick Ryan celebrated a Mass of thanksgiving for 10,000 people after the liberation of Rome?
... that Perplexities after Escher, a composition for heckelphone, string quartet and double bass, is based on five graphic artworks by M. C. Escher?

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