CHAPTER 1 CEVA ' S THEOREM AND MENELAUS ' S THEOREM

Page 1 of 21 CHAPTER 1 CEVA'S THEOREM AND MENELAUS'S THEOREM The purpose of this chapter is to develop a few results that may be used in later chapters. We will begin with a simple but useful theorem concerning the area ratio of two triangles with a common side. With this theorem in hand, we prove the famous Ceva's theorem and Menelaus's theorem. The converses of these two theorems guarantee the existence of the centroid, incenter and orthocenter of any given triangle.

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