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Motivation In Teaching Mathematics

Table 5:

Exercise 2.In a regular hexagonal pyramid MABCDEF in which the side edges equal 4 and the edges of the base equal 1, calculate the distance from the middle of edge BC to face EMD.Solution. In a regular hexagon A B C D E F , B D D E and B D = 3 . Since МО is the altitude of the pyramid, then in right-angled triangle MOD we find M O = 15 . In right-angled triangle MDN we find the apothem of face DME: M N = M D 2 - D E 2 2 = 3 7 2 . Planes M O N and D M E are perpendicular; therefore altitude OH of triangle MON is perpendicular to plane DME. In right-angled triangle MON we find O H = M O O N M N = 15 3 2 : 3 7 2 = 5 7 .
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