# Notes on euclid

He was likely born c. He is rarely mentioned by name by other Greek mathematicians from Archimedes c. This biography is generally believed to be fictitious. Background on ratio and proportion Book V covers the abstract theory of ratio and proportion. A ratio is an Notes on euclid of the relative size of two magnitudes. The propositions in the following book, Book VI, are all geometric and depend on ratios, so the theory of ratios needs to be developed first.

To get a better understanding of what ratios are in geometry, consider the first proposition VI. It states that triangles of the same height are proportional to their bases, that is to say, one triangle is to another as one base is to the other. A proportion is simply an equality of two ratios.

A simple example is when one base is twice the other, therefore the triangle on that base is also twice the triangle on the other base.

This ratio of 2: Indeed, any ratio equal to a ratio of two numbers is easy to comprehend.

## Euclid Biography - Childhood, Life Achievements & Timeline

Given a proportion that says a ratio of lines equals a ratio of numbers, for instance, A: This interpretation is the definition of proportion that appears in Book VII. Either interpretation will do if one of the ratios is a ratio of numbers, and if A: B equals a ratio of numbers that A and B are commensurable, that is, both are measured by a common measure.

Many straight lines, however, are not commensurable. B is not the ratio of numbers. This fact seems to have been discovered by the Pythagoreans, perhaps Hippasus of Metapontum, some time before B.

The difficulty is one of foundations: The solution is that in V. That definition, and the whole theory of ratio and proportion in Book V, are attributed to Eudoxus of Cnidus died. Summary of the propositions The first group of propositions, 1, 2, 3, 5, and 6 only mention multitudes of magnitudes, not ratios. They each either state, or depend strongly on, a distributivity or an associativity. In the following identities, m and n refer to numbers that is, multitudes while letters near the end of the alphabet refer to magnitudes.

Multiplication by numbers distributes over addition of magnitudes. Multiplication by magnitudes distributes over addition of numbers. An associativity of multiplication.

Multiplication by numbers distributes over subtraction of magnitudes. Uses multiplication by magnitudes distributes over subtraction of numbers. The rest of the propositions develop the theory of ratios and proportions starting with basic properties and progressively becoming more advanced.

Substitution of equals in ratios. A converse to V. Transitivity of equal ratios.

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Substitution of equal ratios in inequalities of ratios. Proportional taken jointly implies proportional taken separately.Euclid was a renowned Greek mathematician, known as the ‘Father of Geometry’. This biography profiles his childhood, life, works, achievements and srmvision.com Of Birth: Alexandria.

Nov 12,  · SOURCE: "The History of Geometry to the Time of Euclid: Commentary on Euclid's 'Elements I,'" in A Source Book In Greek Science, edited by Morris R. . Euclid of Alexandria ( – B.C.) Besides being a mathematician in his own right, Euclid is most famous for his treatise The Elements which catalogs and places on a firm foundation much of Greek mathematics.

Not much is known about Euclid’s life. Euclid’s Elements is by far the most famous mathematical work of classical antiquity, and also has the distinction of being the world’s oldest continuously used mathematical textbook.

## Great ideas and gems of mathematics

Little is known about the author, beyond. Euclid of Alexandria ( - B.C.) Besides being a mathematician in his own right, Euclid is most famous for his treatise The Elements which catalogs and places on a firm foundation much of Greek mathematics.

Not much is known about Euclid's life. Even his birthplace and his education are in dispute. We do know. Euclid understood that building a logical and rigorous geometry (and mathematics) depends on the foundation—a foundation that Euclid began in Book I with 23 definitions (such as “a point is that which has no part” and “a line is a length without breadth”), five unproved assumptions that Euclid called postulates (now known as axioms.

Euclid | Biography, Contributions, & Facts | srmvision.com