Early+Trigonometry-+Amber+Sime

Early trigonometry The ancient Egyptians and Babylonians had known of theorems on the ratios of the sides of similar triangles for a really long time. But pre-Hellenic societies lacked the technology of an angle measurement, so they measured the sides of the triangles.The Babylonian astronomers kept detailed records on the rising and the setting of stars, the motion of the planets, and the solar and lunar eclipses, all of which required familiarity with angles. The Egyptians, on the other hand, used a primitive form of trigonometry for building pyramids in the 2nd millennium BC, The Rhind Mathematical Papyrus, contains the following problem related to trigonometry: "If a pyramid is 250 cubits high and the side of its base 360 cubits long, what is its seked?" Ahmes' solution to the problem is the ratio of half the side of the base of the pyramid to its height, or the run-to-rise ratio of its face. In other words, the quantity he found for the seked is the cotangent of the angle to the base of the pyramid and its face.