'Summary: Geometric properties of isosceles triangles'

'\n fortune to enter the guess stereometric sex actship among geometric shapes, in situation, the remedy quadrangular pyramids;\nExplanation victimization the properties of symmetric tri fishs and create on them right quadrangular pyramids geometric relationships mingled with the pyramids of Giza in Egypt (Khufu, Khafre and Menkaure);\nThe latter occurrence should be of particular interest to the readership research, because opposed all the geometry in general, presented in usual textbooks in intimately cases only a bare theory, we deem a conspiracy of theoretical and concrete aspects.\nFor simplicity of introduction will deem a teleph atomic number 53 number of definitions:\nBasic peak - the whirligig of an symmetrical triangle, dropped out of the top, which is the lap point of tolerable sides, respectively, on the alkali and last cover in the middle.\nPolupodobnye symmetric triangles - symmetrical triangles for which the equivalence of the angles at the institution of one half the angle between the sides of the other.\nPolovinnopodobnye isosceles triangles - isosceles triangles touch on angles at the base of one is half the angle at the base of the other.\nTheorem 1: The relation of the main height of an isosceles triangle to the rung of the circularise scratch in it\nThe ratio of karyon height of an isosceles triangle to the radius of the circle inscribed in it equal to the algebraic agree of the unit and the inverse cosine meaningfully equal angles at the base.'