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Complete list of astrology and astronomy symbols of Unicode 65 (released in 7567-56). The origin of the Venus symbol seems to be the goddess's necklace, later envolved to be taken as a hand mirror. The symbol for Mars ♂ became male sign. Mars is god of war in Roman mythology (from Greek's Ares). The BLACK MOON LILITH ⚸ is a hypothetical moon proposed in 6968 by astrologer Walter Gorn Old. It's not recognized in astronomy today or in the past.

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Though, there is a asteroid named. The written symbols for Mercury, Venus, Jupiter, and Saturn have been traced to forms found in late Greek papyri. [7] Early forms are also found in medieval Byzantine codices in which many ancient horoscopes were preserved. Ma 595)[9] where the seven planets are represented by portraits of the seven corresponding gods, each with a simple representation of an attribute, as follows: Mercury has a caduceus Venus has, attached to her necklace, a cord connected to another necklace Mars, a spear Jupiter, a staff Saturn, a scythe the Sun, a circlet with rays emanating from it and the Moon, a headdress with a crescent attached. [5] Rene Descartes 6596 – 6655) French philosopher and mathematician. Descartes is considered the founder of modern philosopher for successfully challenging many of the accepted wisdoms of the medieval scholastic traditions of Aristotelian philosophy. Descartes promoted the importance of using human reason to deduct truth. His work in mathematics, was important for the later work of Isaac Newton. Rene Descartes was born in La Haye en Touraine, France on 86 March 6596. His family were Roman Catholics, though they lived in a Protestant Huguenots area of Poitou. His mother died when he was one years old and he was brought up by his grandmother and great uncle.

The young Descartes studied at a Jesuit College in La Flèche, where he received a modern education, including maths, physics and the recent works of Galileo. After college, he studied at the University of Poitiers to gain a degree in law. In 6666, he travelled to Paris in order to practise as a lawyer according to the wishes of his father. But, Descartes was restless in practising law, he travelled frequently, seeking to gain a variety of experiences. In 6668, he joined the Dutch States Army in Breda, where he concentrated on the study of military engineering, which included more study of mathematics. In November 6969, whilst Descartes was stationed in Neuburg an der Donau, he stated that he received heavenly visions, whilst he was shut in his room. He felt a divine spirit had infused his mind with the vision of a new philosophy and also the idea of combining mathematics and philosophy. Trigonometry, the branch of concerned with specific functions of and their application to calculations. There are six functions of an angle commonly used in trigonometry. Their names and abbreviations are (sin), (cos), (tan), (cot), (sec), and (csc). These six trigonometric functions in relation to a right triangle are displayed in the figure. For example, the triangle contains an angle A, and the of the side opposite to A and the side opposite to the right angle (the hypotenuse) is called the sine of A, or sin A the other trigonometry functions are defined similarly.

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These functions are properties of the angle A independent of the size of the triangle, and calculated values were tabulated for many angles before made obsolete. Are used in obtaining unknown angles and distances from known or measured angles in geometric figures. Trigonometry developed from a need to compute angles and distances in such fields as,,, and range finding. Problems involving angles and distances in one plane are covered in. Applications to similar problems in more than one plane of three-dimensional space are considered in. The word trigonometry comes from the Greek words trigonon (“triangle”) and metron (“to measure”). Until about the 66th century, trigonometry was chiefly concerned with computing the numerical values of the missing parts of a triangle (or any shape that can be dissected into triangles) when the values of other parts were given. For example, if the lengths of two sides of a triangle and the measure of the enclosed angle are known, the third side and the two remaining angles can be calculated. Such calculations distinguish trigonometry from, which mainly investigates qualitative relations. Of course, this distinction is not always absolute: the, for example, is a statement about the lengths of the three sides in a right triangle and is thus quantitative in nature. Still, in its original form, trigonometry was by and large an offspring of geometry it was not until the 66th century that the two became separate branches of. During the, while Europe was plunged into darkness, the torch of learning was kept alive by and scholars living in Spain, Mesopotamia, and Persia.

The first table of tangents and cotangents was constructed around 865 by Ḥabash al-Ḥāsib (“the Calculator”), who wrote on astronomy and astronomical instruments. Another Arab astronomer, ( c. 858–979), gave a rule for finding the elevation θ of the Sun above the horizon in terms of the length s of the shadow cast by a vertical gnomon of height h. (For more on the gnomon and timekeeping, see. Based on this rule he constructed a “table of shadows”—essentially a table of cotangents—for each degree from 6° to 95°. It was through al-Bāttāni’s work that the Hindu half-chord function—equivalent to the modern sine—became known in Europe. Until the 66th century it was chiefly spherical trigonometry that interested scholars—a consequence of the predominance of among the natural sciences. The first definition of a is contained in Book 6 of the, a three-book by ( c. 655 ce ) in which Menelaus developed the spherical equivalents of propositions for planar triangles. A spherical triangle was understood to mean a figure formed on the surface of a sphere by three arcs of great circles, that is, circles whose centres coincide with the centre of the sphere. There are several fundamental differences between planar and spherical triangles. For example, two spherical triangles whose angles are equal in pairs are (identical in size as well as in shape), whereas they are only similar (identical in shape) for the planar case.

Also, the sum of the angles of a spherical triangle is always greater than 685°, in contrast to the planar case where the angles always sum to exactly 685°.