Pierre de Fermat was born in Beaumont-de-Lomagne, France in August of 1601 and died in 1665. He is considered to be one of the greatest mathematicians of the seventeenth century. Fermat is considered to be one of the 'fathers' of analytic geometry. Fermat along with Blaise Pascal is also considered to be one of the founders of probability theory. Fermat also made contributions in the field of optics and provided a law on light travel and made wrote a few papers about calculus well before Isaac Newton and Gottfried Leibniz were actually born.Fermat's most important work was done in the development of modern number theory which was one of his favorite areas in math. He is best remembered for his number theory, in particular for Fermat's Last Theorem. This theorem states that: xn + yn = zn has no non-zero integer solutions for x, y and z when n is greater than 2.
Fermat almost certainly wrote the marginal note around 1630, when he first studied Diophantus's Arithmetic. It may well be that Fermat realized that his prove was wrong, however, since all his other theorems were stated and restated in challenge problems that Fermat sent to other mathematicians. Although the special cases of n = 3 and n = 4 were issued as challenges the general theorem was never mentioned again by Fermat.
In fact in all the mathematical work left by Fermat there is only one proof. Fermat proves that the area of a right trangle cannot be a square. Meaning that a rational triangle cannot be a rational square. In symbols, there do not exist integers x, y, z with x2 + y2 = z2 such that xy/2 is a square. From this it is easy to deduce the n = 4 case of Fermat's theorem.
The proof of Fermat's Last Theorem marks the end of a mathematical era. Since all of the tools which were brought to bear on the problem still had to be invented in the time of Fermat. Judging by the tenacity with which the problem wa for so long, Fermat's alleged proof seems likely to have been