1、 2017-2018 3 30 1 A 13 12 20 B 5 5 11 C 8 7 15 D 3 8 4 2 A 1 B 2 C 3 D 4 3 A 2 B 3 C 4 D 6 4 ABC C = 90 C 1 2 A 315 B 270 C 180 D 135 5 A B C D 6 Rt ABC C = 90 A AC AB 1-10 11-16 17 18 19 20 21 22 23 3 4 2 1 C B A M N M N 1 2 MN P AP CB D CD = 4 AB = 15 ABD A 15 B 30 C 45 D 60 7 1 2 3 4 1= 2= 3= 4=7
2、5 A A 120 B 115 C 110 D 108 8 A 0 90 B 60 180 C 60 90 D 60 90 9 ABC AB = 5 AC = 6 BC = 4 AB AC D BDC A 8 B 9 C 10 D 11 10 ABC E AC AD BC P AD AD=3 EP CP A 2 B 3 C 4 D 5 3 18 11 P 1 3 y 12 3 5 13 14 ABC BAD BC = AD ABC BAD 7 4 3 2 1 E A B C D 6 P N M D C B A 9 A B C D E 10 A B C D E P 15 A D B C 14 A
3、 B C D E 16 A D B C A 15 ABC A = 60 ABC DE A BC A A EC = 70 A DE 16 AD ABC BC AB = 4 AC = 6 AD 7 72 17 10 ABC 3 2 1 3 2 1 1 ABC x A1B1C1 A B C A1 B1 C1 2 AA1 CC1 AA1 C1C 18 10 ACB ECD A C D BD AE AE BD F AE BD 19 10 ABC AB =AC BAC = 100 AB AB D BC E AEC F E D C B A A B D C E C B A y x O 20 10 ABC AB
4、C = 90 AB = 7 AC = 25 BC = 24 P P AB P A B C 21 10 ABC AB =AC E AB F AC BE=CF EF BC D DE=DF 22 10 A P 75 7 B P 60 3.8 A C D F E B 75 60 A B P 23 12 ABC AB =AC=2 B = 40 D BC B C AD ADE = 40 DE AC E 1 BDA = 115 BAD= DEC = D B C BDA 2 DC ABD DCE 3 D ADE BDA 40 40 A B C E D 2017-2018 3 30 1 2 3 4 5 6 7
5、8 9 10 A B C B C B A D C B 3 15 11 12 13 14 15 16 1 3 11 13 135 AC=BD DAB= CBA 65 10 2 AD 17 1 4 2 AA1 CC1 A1 -3 -2 B1 -1 3 C1 2 -1 AA1 x CC1 x AA1=4 CC1=2 AA1C1C h 5 8 AA1C1C 2 1 AA1+CC1 h= 2 1 2+4 5=15 10 18 AE=BD 2 ACB ECD AC=BC CE=CD ACE= DCE=90 6 AEC BDC AC=BC ACE= DCE=90 CE=CD AEC BDC AE=BD 10
6、 19 ACB AB=AC BAC=100 B= C= 2 100 180 =40 4 DE AB AE=EB 1= B=40 8 AEC ABE AEC= B+ 1=80 10 20 P PD AB D PE BC E PF AC F P ABC PD=PE=PF 4 S ABC = S PAB + S PBC + S PAC = 2 1 PD AB+ 2 1 PE BC+ 2 1 PF AC = 2 1 PD AB+BC+AC = 2 1 PD 7+25+24 =28PD 7 ABC=90 S ABC = 2 1 AB BC= 2 1 7 24=7 12 7 12=28PD PD=3 P
7、AB 3 10 21 E EM AF BC M 1= ACB 2= F 2 AB=AC B= ACB 1= B BE=ME 5 BE=CF ME=CF 6 DME DCF 2, 3 4, . F ME CF ? ? = DME DCF 9 DE=DF 10 22 2 1=90 - 60 = 30 2=90 - 75 =15 4 P PC AB AB C 1 ABP 3= 1- 2=15 3= 2 PB=AB=7 8 Rt PBC 1= 30 PC= 2 1 PB=3.5 3.8 10 23 1 25 1 115 3 4 2 DC=2 ABD DCE 5 ABC AB=AC B=40 C= B=40 6 ADC ABD ADC= 1+ B 1= ADC - B= ADC-40 2= ADC-40 1= 2 8 ABD DCE 1 2, , . BC AB DC ? ? = ABD DCE 10 3 BDA=110 80 12
