1. HİS LİFE AND HİS STUDİES
RENE DESCARTES

2. PERSONAL LİFE
Rene Descartes was born at La Haye in Touraine on 31 March When he was one year old, his mother Jeanne Brochard died of tuberculosis. His father Joachim was a member in the provincial parliament. Reaches the age of ten, due to the city of Anjou and later the La FLECHE is one of the best schools in Europe will indicate, Royal Henry-Le-Grand has been sent to a Jesuit college.Teachers were expected to go to boarding school.Until he feels better he was in bed.So, he focused mathematical studies.he learned the Latin language and Greek because of education in school focused greek and the Latin language.

3. PERSONAL LİFE
In the summer of 1618 he joined the army of Maurice of Nassau in the Dutch Republic. On 10 November 1618, while walking through Breda,Descartes met Isaac Beeckman, who sparked his interest in mathematics and the new physics, particularly the problem of the fall of heavy bodies. While in the service of the Duke Maximilian of Bavaria, Descartes was present at the Battle of the White Mountain outside Prague, in November In 1622 he returned to France, and during the next few years spent time in Paris and other parts of Europe. He arrived in La Haye in 1623, selling all of his property, investing this remuneration in bonds which provided Descartes with a comfortable income for the rest of his life. Descartes was present at the siege of La Rochelle by Cardinal Richelieu in 1627.
He returned to the Dutch Republic in 1628, where he lived until September In April 1629 he joined the University of Franeker and the next year, under the name "Poitevin", he enrolled at the Leiden University to study mathematics with Jacob Golius and astronomy with Martin Hortensius

4. PERSONAL LİFE
In October 1630 he had a falling out with Beeckman, whom he accused of plagiarizing some of his ideas. In Amsterdam, he had a relationship with a servant girl, Helène Jans, with whom he had a daughter, Francine, who was born in 1635 in Deventer, at which time Descartes taught at the Utrecht University. Francine Descartes died in 1640 in Amersfoort.
While in the Netherlands he changed his address frequently, living among other places in Dordrecht (1628), Franeker (1629), Amsterdam (1629–30), Leiden (1630), Amsterdam (1630–2), Deventer (1632–4), Amsterdam (1634-5), Utrecht (1635-6), Leiden (1636), Egmond (1636–8), Santpoort (1638–1640), Leiden (1640–1), Endegeest (a castle near Oegstgeest) (1641-3), and finally for an extended time in Egmond-Binnen (1643–9).
Despite these frequent moves he wrote all his major work during his 20 plus years in the Netherlands, where he managed to revolutionize mathematics and philosophy. In 1633, Galileo was condemned by the Roman Catholic Church, and Descartes abandoned plans to publish Treatise on the World, his work of the previous four years. "Discourse on the Method" was published in In it Descartes lays out four rules of thought, meant to ensure that our knowledge rests upon a firm foundation.

5. CARTESİAN COORDİNATE SYSTEM
Illustration of a Cartesian coordinate plane. Four points are marked and labeled with their coordinates: (2,3) in green, (−3,1) in red, (−1.5,−2.5) in blue, and the origin (0,0) in purple.

6. CARTESİAN COORDİNATE SYSTEM
Cartesian coordinate system with the circle of radius 2 centered at the origin marked in red. The equation of the circle is x2 + y2 = 22.

7. CARTESİAN COORDİNATE SYSTEM
A three dimensional Cartesian coordinate system, with origin O and axis lines X, Y and Z, oriented as shown by the arrows. The tic marks on the axes are one length unit apart. The black dot shows the point with coordinates X = 2, Y = 3, and Z = 4, or (2,3,4).

8. CARTESİAN COORDİNATE SYSTEM
The coordinate surfaces of the Cartesian coordinates (x, y, z). The z-axis is vertical and the x-axis is highlighted in green. Thus, the red plane shows the points with x=1, the blue plane shows the points with z=1, and the yellow plane shows the points with y=-1. The three surfaces intersect at the point P (shown as a black sphere) with the Cartesian coordinates (1, -1, 1).