ᠴᠢᠪᠠᠭᠠ ᠮᠤᠩᠭᠤᠯ ᠲᠤᠮᠳᠠᠳᠤ ᠰᠤᠷᠭᠠᠭᠤᠯᠢ — ᠲᠤᠭᠠᠨ ᠤ ᠤᠬᠠᠭᠠᠨ — ᠨᠠᠢᠮᠠ ᠤᠨ — ᠲᠤᠤᠷᠠᠳᠤ — ᠦᠷᠴᠠᠶᠢᠬᠤ — 18.2.2🎬 ᠤᠮᠪ (1) .pptx
 ᠵᠢᠰᠢᠬᠦᠯᠵᠢᠨ ᠤᠤ ︖,ᠲᠠᠢ ᠪᠤᠢ ︖ ᠶᠠᠮᠠᠷ ᠬᠤᠯᠪᠤᠠᠠᠳ᠋ᠠᠯ ᠲᠠᠯᠠ ᠨᠢ,ᠨᠠᠢ᠍ᠮᠠᠳᠤᠭᠠᠷ ᠣᠨ ( ᠲᠤᠤᠷᠠᠳᠤ ᠲᠡᠪᠳᠡᠷ ),ᠠᠯᠪᠠᠨ ᠵᠢᠷᠤᠮ ᠤᠨ ᠰᠤᠷᠭᠠᠨ ᠭᠦᠮᠦᠵᠢᠯ ᠦᠨ ᠰᠤᠷᠬᠤ ᠪᠢᠴᠢᠭ᠌,ᠲᠣᠭᠠᠨ ᠤ ᠤᠬᠠᠭᠠᠨ,ᠠᠷᠤ ᠬᠣᠷᠴᠢᠨ ᠬᠣᠰᠢᠭᠤᠨ ᠣ ᠴᠢᠪᠠᠭᠠ ᠮᠣᠩᠭᠤᠯ ᠦᠨᠳᠦᠰᠦᠲᠡᠨ ᠣ ᠳᠤᠮᠳᠠᠳᠤ ᠰᠤᠷᠭᠠᠭᠤᠯᠢ ᠦᠷᠴᠠᠢᠬᠤ,18.2 ᠤᠨᠴᠠᠭᠠᠢ ᠵᠢᠰᠢᠭᠦᠯᠵᠢᠨ,18.2.2 ᠷᠤᠮᠪ (1),,ᠵᠢᠰᠢᠭᠦᠯᠵᠢᠨ,,ᠷᠣᠮᠪ,,ᠷᠤᠮᠪ ᠤᠨ ᠲᠤᠳᠤᠷᠬᠠᠶᠢᠯᠠᠯᠲᠠ,1.ᠷᠤᠮᠪ ᠲᠦ ᠶᠠᠮᠠᠷ ᠶᠠᠮᠠᠷ ᠲᠡᠨᠭᠴᠡᠭᠦᠦ ᠬᠡᠷᠴᠢᠮ ᠪᠠᠢᠢᠬᠤ ᠪᠤᠢ ︖ 2.ᠷᠤᠮᠪ ᠲᠦ ᠶᠠᠮᠠᠷ ᠶᠠᠮᠠᠷ ᠲᠡᠨᠭᠴᠡᠭᠦᠦ ᠦᠨᠴᠦᠭ ᠪᠠᠢᠢᠬᠤ ᠪᠤᠢ ︖ 3.ᠷᠤᠮᠪ ᠦᠨ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠨᠢ ᠶᠠᠮᠠᠷ ᠤᠨᠴᠠᠭᠠᠢ ᠬᠤᠯᠪᠤᠠᠠᠳᠠᠯ ᠲᠠᠢ ᠪᠤᠢ ︖ 4.ᠷᠤᠮᠪ ᠲᠡᠩᠭᠡᠯᠢᠭ ᠲᠦ ᠲᠡᠭᠰᠢ ᠬᠡᠮᠳᠡᠢ ᠵᠢᠷᠤᠭ ᠲᠦᠷᠰᠦ ᠤᠤ︖ ᠲᠡᠭᠦᠨ ᠦ ᠲᠡᠭᠰᠢ ᠬᠡᠮ ᠦᠨ ᠲᠡᠩᠭᠡᠯᠢᠭ ᠨᠢ ︖,1.AB=CD=AD=BC OA=OC , OB=OD,2.∠DAB=∠BCD , ∠ABC =∠CDA, ∠1=∠2=∠3=∠4, ∠5=∠6=∠7=∠8,3.𝐴𝐶⊥𝐵𝐷 AO=CO,BO=DO,4.ᠲᠡᠩᠭᠡᠯᠢᠭ ᠲᠦ ᠲᠡᠭᠰᠢ ᠬᠡᠮᠳᠡᠢ ᠵᠢᠷᠤᠭ ᠲᠦᠷᠰᠦ ᠮᠦᠨ ᠃ ᠬᠤᠶᠠᠷ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠶᠢᠨ ᠤᠷᠤᠰᠢᠵᠤ ᠪᠠᠢᠢᠭᠠ ᠰᠢᠯᠤᠭᠤᠨ,,,1. ᠷᠣᠮᠪ ᠤᠨ ᠲᠦᠷᠪᠡᠨ ᠲᠠᠯᠠ ᠨᠢ ᠴᠦᠮ ᠲᠡᠩᠴᠡᠭᠦᠦ ᠃ 2. ᠷᠣᠮᠪ ᠤᠨ ᠬᠣᠶᠠᠷ ᠲᠠᠰᠢᠭᠣᠪᠴᠢ ᠨᠢ ᠬᠠᠷᠢᠯᠴᠠᠨ ᠡᠭᠴᠡ ᠪᠣᠯᠬᠣ ᠪᠦᠭᠡᠳ ᠲᠠᠰᠢᠭᠣᠪᠴᠢ ᠨᠢᠭᠡ ᠪᠦᠷᠢ ᠨᠢ ᠨᠢᠭᠡ ᠬᠣᠣᠰ ᠡᠰᠡᠷᠭᠦ ᠦᠨᠴᠦᠭ ᠶᠢᠡᠨ ᠲᠠᠯᠠᠯᠠᠨ ᠬᠣᠪᠢᠶᠠᠨᠠ ᠃,𝐴𝐵∥𝐶𝐷,𝐴𝐷∥𝐵𝐶 AB=𝐶𝐷,𝐴𝐷=𝐵𝐶,∠𝐴=∠𝐶,∠𝐵=∠𝐷 ∠𝐴+∠𝐷= 180 ° , ∠𝐴+∠= 180 °,𝑂𝐴=𝑂𝐶, 𝑂𝐵=𝑂𝐷,ᠷᠤᠮᠪ ᠤᠨ ᠰᠢᠨᠵᠢ ᠴᠢᠨᠠᠷ,𝐴𝐶⊥𝐵𝐷 AO=CO,BO=DO,∠DAB=∠BCD ∠ABC=∠CDA ∠1=∠2=∠3=∠4 ∠5=∠6=∠7=∠8,𝐴𝐵∥𝐶𝐷,𝐴𝐷∥𝐵𝐶 AB=CD=AD=BC,1. ᠷᠣᠮᠪ ᠤᠨ ᠲᠦᠷᠪᠡᠨ ᠲᠠᠯᠠ ᠨᠢ ᠴᠦᠮ ᠲᠡᠩᠴᠡᠭᠦᠦ ᠃ 2. ᠷᠣᠮᠪ ᠤᠨ ᠬᠣᠶᠠᠷ ᠲᠠᠰᠢᠭᠣᠪᠴᠢ ᠨᠢ ᠬᠠᠷᠢᠯᠴᠠᠨ ᠡᠭᠴᠡ ᠪᠣᠯᠬᠣ ᠪᠦᠭᠡᠳ ᠲᠠᠰᠢᠭᠣᠪᠴᠢ ᠨᠢᠭᠡ ᠪᠦᠷᠢ ᠨᠢ ᠨᠢᠭᠡ ᠬᠣᠣᠰ ᠡᠰᠡᠷᠭᠦ ᠦᠨᠴᠦᠭ ᠶᠢᠡᠨ ᠲᠠᠯᠠᠯᠠᠨ ᠬᠣᠪᠢᠶᠠᠨᠠ ᠃,ᠷᠤᠮᠪ ᠤᠨ ᠲᠠᠯᠠᠪᠠᠢ,S = 1 2 BD∙ AC,ᠬᠠᠭᠠᠰ ᠲᠠᠢ ᠲᠡᠩᠴᠡᠨᠡ ᠃ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠶᠢᠨ ᠦᠷᠡᠵᠢᠪᠦᠷᠢ ᠶᠢᠨ ᠷᠤᠮᠪ ᠤᠨ ᠲᠠᠯᠠᠪᠠᠢ ᠨᠢ ᠬᠤᠶᠠᠷ,= 1 2 BD∙AO+ 1 2 BD∙CO,= 1 2 BD∙(AO+CO),= 1 2 BD∙AC,ᠪᠠᠳ᠋ᠤᠳᠬᠠᠯ ᠄,∠BAC= ᠭᠷᠠᠳᠦ᠋ᠰ ᠃ 2. ᠷᠤᠮᠪABCD ᠳ᠋ᠤ ∠ABC=60° ᠪᠤᠯ ᠲᠡᠭᠡᠪᠡᠯ ᠲᠡᠭᠦᠨ ᠦ ᠲᠠᠯᠠ ᠶᠢᠨ ᠤᠷᠳᠤ ᠨᠢ cm᠃ 1.ᠨᠢᠬᠡ ᠷᠤᠮᠪ ᠤᠨ ᠬᠦᠷᠢᠶᠡᠨ ᠦ ᠤᠷᠳᠤ ᠨᠢ 12cm,,ᠤᠷᠳᠤ ᠨᠢ , ᠲᠤᠰ 6cm ᠪᠠ 8cm ᠪᠣᠯ ᠲᠡᠭᠦᠨ ᠦ ᠲᠠᠯᠠ ᠶᠢᠨ 3.ᠨᠢᠬᠡ ᠷᠤᠮᠪ ᠤᠨ ᠬᠤᠶᠠᠷ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠶᠢᠨ ᠤᠷᠳᠤ ᠨᠢ ᠲᠤᠰ,A.10cm B.7cm C. 5cm D.4cm,3cm,60,C,3,4,ᠵᠢᠱᠢᠶᠡ ᠄ ᠵᠢᠷᠤᠭ ᠮᠡᠳᠦ ᠂ ᠷᠤᠮᠪ ᠬᠡᠯᠪᠡᠷᠢᠳᠡᠢ ᠴᠡᠴᠡᠭᠯᠢᠭABCD ᠶᠢᠨ ᠲᠠᠯᠠ ᠶᠢᠨ ᠤᠷᠳᠤ ᠨᠢ 20m, ∠ABC=60°ᠷᠤᠮᠪ ᠤᠨ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠲᠠᠭᠠᠤ ᠬᠤᠶᠠᠷ ᠵᠦᠷᠢᠭ AC ᠪᠠ BD ᠵᠠᠰᠠᠪᠠ ᠃ ᠬᠤᠶᠠᠷ ᠵᠦᠷᠢᠭ ᠦᠨ ᠤᠷᠳᠤ ᠪᠠ ᠴᠢᠴᠢᠭᠯᠢᠭ ᠦᠨ ᠲᠠᠯᠠᠪᠠᠢ ᠶᠢ ᠤᠯ ᠃( ᠳ᠋ᠦᠩ ᠦᠨ ᠠᠷᠪᠠᠳᠤ ᠶᠢᠨ ᠪᠤᠲᠠᠷᠬᠠᠢ ᠶᠢᠨ ᠴᠡᠭ ᠦᠨ ᠠᠷᠤ ᠳᠤ ᠨᠢᠭᠡ ᠤᠷᠤᠨ ᠦᠯᠡᠳᠡᠭᠡ),ᠪᠤᠳᠤᠬᠤ ᠨᠢ ᠄,∴ AC⊥BD, ∠ABO = 1 2 ∠ABC = 1 2 ×60°=30°,BO= 𝐴𝐵 2 − 𝐴𝑂 2 = 20 2 − 10 2 =10 3 (m),ᠡᠢᠮᠦ ᠡᠴᠡ᠄ ᠴᠡᠴᠡᠭᠯᠢᠭ ᠤᠨ ᠬᠤᠶᠠᠷ ᠵᠦᠷᠢᠭ ᠦᠨ ᠤᠷᠳᠤ ᠨᠢ ᠲᠤᠰ ᠲᠤᠰ,ᠴᠡᠴᠡᠭᠯᠢᠭ ᠤᠨ ᠲᠠᠯᠠᠪᠠᠢ ᠨᠢ,AC=2AO=20m,BD=2OB=20 3 ≈20×1 .732 ≈34.64 m,ᠪᠠᠳ᠋ᠤᠳᠬᠠᠯ ᠄,(3) ᠷᠤᠮᠪ ᠦᠨ ᠲᠠᠯᠠᠪᠠᠢ ᠶᠢ ᠤᠯ ᠃ (2) ᠲᠠᠰᠢᠭᠤᠪᠴᠢ AC,BD ᠤᠷᠳᠤ ᠶᠢ ᠤᠯ ᠃ (1)∠𝐴𝐵𝐶 ᠶᠢᠨ ᠭᠷᠠᠳᠦ᠋ᠰ ᠦᠨ ᠲᠣᠭᠠ ᠶᠢ ᠤᠯ ᠃ ᠴᠡᠭ ᠂ DE⊥AB,AE=2; ᠤᠯᠬᠤ ᠨᠢ᠄ 4. ᠷᠤᠮᠪ ABCD ᠳᠤ ᠂ E ᠪᠤᠯ AB ᠶᠢᠨ ᠲᠤᠮᠳᠠ,ᠪᠤᠳᠤᠬᠤ ᠨᠢ ᠄,(1),∴AD=AB=BD,∴ ∠DBA= 60 ° ∴ ∠ABC=120 °,(2),2,∵AE=2, ∴ AB=4 ∴ BD=AB=4,AO= 𝐴𝐵 2 − 𝐵𝑂 2 = 4 2 − 2 2 =2 3,∴ AC=4 3,(3),ᠷᠤᠮᠪ ᠤᠨ ᠰᠢᠨᠵᠢ ᠴᠢᠨᠠᠷ ᠄,ᠲᠠᠯᠠ,,ᠦᠨᠴᠦᠭ,ᠵᠡᠷᠭᠡᠴᠡᠭᠡ ᠲᠠᠯᠠ ᠨᠢ ᠡᠰᠡᠷᠭᠦ,ᠲᠡᠨᠭᠴᠡᠭᠦᠦ ᠲᠠᠯᠠ ᠨᠢ ᠲᠦᠷᠪᠡᠨ,ᠲᠡᠨᠭᠴᠡᠭᠦᠦ ᠦᠨᠴᠦᠭ ᠨᠢ ᠡᠰᠡᠷᠭᠦ,,ᠨᠦᠬᠦᠪᠦᠷᠢ ᠦᠨᠴᠦᠭ ᠨᠢ ᠵᠡᠷᠭᠡᠯᠡᠳᠡᠭᠡ,ᠲᠠᠰᠢᠭᠤᠪᠴᠢ,,ᠬᠤᠪᠢᠶᠠᠨᠠ ᠲᠠᠯᠠᠯᠠᠨ ᠡᠭᠴᠡ ᠬᠠᠷᠢᠯᠴᠠᠨ,ᠬᠤᠪᠢᠶᠠᠨᠠ ᠲᠠᠯᠠᠯᠠᠨ ᠦᠨᠴᠦᠭ ᠢᠶᠡᠨ ᠡᠰᠡᠷᠭᠦ ᠨᠢᠬᠡᠪᠦᠷᠢ ᠨᠢ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ,ᠬᠤᠶᠠᠷ ᠲᠠᠰᠢᠭᠤᠪᠴᠢ ᠶᠢᠨ ᠦᠷᠡᠵᠢᠪᠦᠷᠢ ᠶᠢᠨ ᠬᠠᠭᠠᠰ ᠰᠠᠭᠤᠷᠢ × ᠦᠨᠳᠦᠷ = ᠷᠤᠮᠪ ᠤᠨ ᠲᠠᠯᠠᠪᠠᠢ ᠄,,ᠪᠤᠯᠪᠠᠰᠤᠷᠠᠯ ᠄ ᠲᠡᠪᠲᠡᠷ ᠦᠨ 68 ᠨᠢᠭᠤᠷ ᠤᠨ1,2 ᠳ᠋ᠤᠭᠠᠷ ᠰᠡᠳᠦᠪ ᠲᠠᠰᠬᠠᠯ ᠄ᠲᠡᠪᠲᠡᠷ ᠦᠨ ᠤ72 ᠨᠢᠭᠤᠷ ᠤᠨ5,11 ᠳ᠋ᠤᠭᠠᠷ ᠰᠡᠳᠦᠪ,