trigonometry summary

Leonhard Euler was a Swiss mathematician and physicist, one of the founders of pure mathematics. He not only made decisive and formative contributions to the subjects of geometry, calculus, mechanics, and number theory but also developed methods for solving problems in observational astronomy and

Hipparchus was a Greek astronomer and mathematician who made fundamental contributions to the advancement of astronomy as a mathematical science and to the foundations of trigonometry. Although he is commonly ranked among the greatest scientists of antiquity, very little is known about his life,