分类30圆的有关性质(含解析)

分类30圆的有关性质(含解析)

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时间:2023-07-02

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19B“ஹO)A.20°B.25°C.30°D.50°ூὃ௃M5ᙊᕜᳮNMCᑗ5ḄឋMூG⚪௃55ARᙊᨵᐵḄxyᐵzN67}ᳮ~ூᑖ᪆௃mn஺4,᪷Xᑗ5ḄឋMYᑮNQ4O=90஺4®NAOP,᪷X#ῪPQḄឋMஹ¯5ḄឋM4®NBOC,᪷Xᙊᕜᳮᓽ].ூ௃mn஺4,(஺Ḅᑗ5:.OA±AP,ZPAO=90°,•.ZAOP=90°-ZP=80°,OA=OB,.\ZOAB=ZOBA=50°,OCI/AB,ZBOC=ZOBA=50°fᵫᙊᕜᳮYZBAC=-ZBOC=25°,2ᦑ⌱B.

20Bூ௃⚪ὃḄ(ᑗ5ḄឋMஹᙊᕜᳮஹ¯5ḄឋMஹ#ῪPQḄឋMᙊḄᑗ5ᚖ9ᑗḄ(⚪Ḅᐵ'.2.2020•¨©T8.4ᑖC᝞EAABC(஺ḄᑁnPQAB=BC,ZE4c=30஺AD(4=8,ᑣACḄ7lbCOA.4B.46C.-A/3D.2733ூὃ௃MAPQḄ᜜nᙊR᜜³N´4ᙊ³ஹµஹ¶ḄᐵzNM5ᙊᕜᳮூG⚪௃559ᙊḄᨵᐵᭆJKឋMN67}ᳮ~ூᑖ᪆௃mn8,᪷X#ῪPQḄឋMYᑮNACB=N5AC=30஺᪷XᙊᑁncQḄឋMYᑮ"=180஺-28=60஺4YNC40=3O஺᪷XPQḄឋMᓽ]Yᑮ^.ூ௃mnCD,AB=BC,ZZMC=30°,/.ZACB=ZBAC=30°,/.ZB=180°-30°-30°=120°,/.ZD=180o-ZB=60°,.-.ZC4£>=30°,

21A£(/.ZACD=90°,AD=8,.-.CD=-AD=4,2AC=yjAD2-CD2=Jg-G=4^,ᦑ⌱B.ூ௃⚪ὃPQḄ᜜nᙊR᜜³ᙊᕜᳮ¸30஺ḄPQḄឋM,!"ᳮ¥¦Ḅ%¹EQ(⚪Ḅᐵ'.3.2020•º»T8.3ᑖC¼ᘤ¾v¿᤮ÁḄxy᝞EᡠÂᙠAAOBÃ5OCABD,ᑣNADCḄvᦪlbCA.60°B.70°C.80°D.85°ூὃ௃M5ᙊᕜᳮூG⚪௃66+~N559ᙊḄᨵᐵᭆJKឋMூᑖ᪆௃᪷X#ῪPQḄឋMPQḄ᜜ḄឋMᓽ]Yᑮ^.ூ௃OA=OB,ZAOB=140°,ZA=ZB=g180°-140°=20°,ZAOC=60°,/.ZADC=ZA+ZAOC=200+60°=80°,

22ᦑ⌱c.ூ௃⚪ὃᙊᕜᳮ#ῪPQḄឋMPQ᜜ḄឋM¥¦Ḅ%¹EQ(⚪Ḅᐵ'.1.2020▷ÅT9,3ᑖC᝞EAABCᑁn9஺஺ZA=50°.E(8cḄmnOEÆ7஺஺9஺mnBQ,ᑣ/஺ḄᜧÈlbCA.55°B.65°C.60°D.75°ூὃ௃M5ᙊᕜᳮNMAPQḄ᜜nᙊR᜜³.ூG⚪௃559ᙊḄᨵᐵᭆJKឋMN67}ᳮ~.ூᑖ᪆௃mnC஺᪷XᙊᑁncQḄឋMYᑮNCZ8=180஺-N4=130஺᪷XᚖᳮYᑮOO_L8C,BD=CD,᪷X#ῪPQḄឋMᓽ]Yᑮ^.ூ௃mnCD,,/ZA=50°,AZCDS=1800-NA=130°,(BCḄODA.BC,.BD=CD,.ZODB=ZODC=-NBDC=65,ூ௃⚪ὃPQḄ᜜nᙊR᜜³ᙊᑁncQḄឋMᚖᳮ#ῪPQḄឋM¥¦Ḅᳮ⚪T(⚪Ḅᐵ'.

231.2020ÉT7,3ᑖC᝞E஺AB=AC,NABC=70஺.ᑣNBOCḄvᦪlbCA.100°B.90°C.80°D.70°ூὃ௃M5ᙊᕜᳮNM4ᙊ³ஹµஹ¶ḄᐵzூG⚪௃64ÊËÌN559ᙊḄᨵᐵᭆJKឋMூᑖ᪆௃ᐜ᪷XᙊᕜᳮYᑮNA8C=N4C8=70஺ÍᑭᵨPQᑁ¢®ZA=40°,ᯠÏ᪷XᙊᕜᳮYᑮNBOCḄvᦪ.ூ௃AB=AC,...ZABCÐ=70°,.'.ZA=180°-70°-70°=40°,.-.ZBOC=2ZA=80°.ᦑ⌱C.ூ௃⚪ὃᙊᕜᳮᙠÑᙊᡈ#ᙊѵᡈ#µᡠÓḄᙊᕜÔ#Õ#9ÖᩩµᡠÓḄᙊ³ḄF.6.1.2020ᓅÙT4,2ᑖCÚᑡEQÜ(³ÓÝEQÞ(ßÓÝEQḄ(bCூὃ௃P3ßÓÝEQNR5³ÓÝEQூG⚪௃558àஹáâRÓÝN64ÊËÌூᑖ᪆௃᪷XßÓÝEQR³ÓÝEQḄᭆJ4.

24ூ௃AஹÜã(ßÓÝEQÞã(³ÓÝEQᦑä⌱⚗ãᔠ⚪TN8ஹÜã(ßÓÝEQÞã(³ÓÝEQᦑä⌱⚗ãᔠ⚪TNCஹã(ßÓÝEQ(³ÓÝEQãᔠ⚪TN஺ஹÜ(³ÓÝEQç(ßÓÝEQèᔠ⚪T.ᦑ⌱D.ூ௃⚪ὃ³ÓÝEQ¢ßÓÝEQḄ$%ᐵ'(é³ÓÝEQRßÓÝEQḄᭆJ.ßÓÝEQḄᐵ'(êëÓÝßEQìᑖᢚîÏ]eᔠ³ÓÝEQ(⌕êëÓݳEQáâ180஺ÏRðEeᔠ.2.b2020ñòT4,4ᑖCÚᑡó®Ḅ#PQஹ¯cQஹᙊKᡧQÜ(ßÓÝEQç(³ÓÝEQḄ(bCூὃ௃R5³ÓÝEQNP3ßÓÝEQூG⚪௃55Fᢗ÷RøEN64ÊËÌூᑖ᪆௃᪷XßÓÝEQR³ÓÝEQḄᭆJ4.ூ௃A.#PQ(ßÓÝEQã(³ÓÝEQNB.¯cQã(ßÓÝEQ(³ÓÝEQNC.ᙊÜ(ßÓÝEQç(³ÓÝEQND.ᡧQ(ßÓÝEQã(³ÓÝEQ.ᦑ⌱C.ூ௃ä⚪ù⌕ὃ³ÓÝEQRßÓÝEQḄᭆJ.ßÓÝEQḄᐵ'(êëÓÝßEQìᑖᢚîÏ]eᔠ³ÓÝEQ(⌕êëÓݳáâ180vÏìᑖeᔠ.7.1.b2020©úT9,4ᑖCû$A,B,Cᙠ஺ᑣÚᑡü⚪lýü⚪Ḅ(bA.p08ᑖ¶AC,ᑣcQQ48C(¯cQ

25B.pcQ஺ABC(¯cQᑣ=120஺C.pNABC=120஺ᑣ¶ACᑖ08D.p¶ACᑖ08,ᑣ08ᑖ¶ACூὃ௃O1ü⚪RᳮூG⚪௃67}ᳮ~N559ᙊḄᨵᐵᭆJKឋMூᑖ᪆௃᪷Xᚖᳮ¯cQḄឋMᑨþᓽ].ூ௃Aஹ᝞EBpOBᑖ¶AC,ᑣcQ஺ABCãF(¯cQNðü⚪(Ꮇ⚪;BஹQ4BCᑣAB=OC,OA=BC,OA=OB=OC,:.AB=OA=OB=BC=OC,..ZABO=NO3C=60°,:.ZABC=120°,⚪;NABC=120஺ᑣACᑖOB,⚪Ꮇ⚪;Dஹ᝞ACᑖ08,ᑣ08ᑖAC,⚪Ꮇ⚪;

26ᦑ⌱B.ூ௃!⚪ὃ#Ḅ⚪ḄᎷᑨ&'(Ḅ⚪)⚪┯+Ḅ⚪),Ꮇ⚪.ᑨ&⚪ḄᎷᐵ/⌕1៉3!4Ḅឋ6ᳮ.1.202089:;T4,3ᑖ<᝞=>438ᑁ@AO,ZABC=1O°,ᑣN/CCḄBᦪD

27AB=48,:.BD=-AB=-x48=24,22஺Ḅcd52,,-.OH=OC=26,ᙠRtAOBD4OD=JOB2-BD?=126?-24,=10,CD=OC-OD=26-10=16(CTO),ூ௃!⚪ὃ#]ᚖᳮஹᳮ{>H᪷T⚪᪀⌼cG}G[\⚪Ḅᐵ/.2.2020ᵞᾓT9,3ᑖ<᝞A஺8CcAC=2,AB=4,A.2yB.C.2D.Mூὃ௃M5ᙊᕜGᳮூI⚪௃559ᙊḄᨵᐵᭆLMឋ6H554{Ὺ}G~cG}GH69yᵨூᑖ᪆௃ᐜ᪷TᙊᕜGWN8AC=ZD=90஺᪷TᳮᓽVWYZ.ூ[\௃[஺ᙠ஺ᑖBC,BD=CD,BCOḄc,

28:.ZBAC=ZD=90°,AC=2,AB=4,BC=72?+4?=2⍩,RtABDC4DC2+BD1=BC2,20c2=20,DC=y/10,ᦑ⌱D.ூ௃!⚪ὃ#ᙊᕜGᳮᳮ{>[⚪Ḅᐵ/ᮣ£Nᵨᡠ¤>[¥¦⚪,¤§ᑭᵨᳮ©ḄªA4ὃ«ὃ⚪¬.2.202089T8,3ᑖ<᝞O{AABCḄᑁᑗᙊᑖ¯ᑗ43,BC,ACAE,F,D,P஺FᑣNEP°ḄBᦪD

29NEPF=-NEOF=60°,2ᦑ⌱B.ூ௃!⚪ὃ#}GḄᑁᑗᙊ~ᑁ±ᑗḄឋ6ᙊᕜGᳮ{>[⚪Ḅᐵ/1^_`´!>ªA4ὃ«ὃ⚪¬.3.202089µ;T9,3ᑖ<᝞=>3c஺Ḅc041.஺ᙠ¶·ACD~A,C¸ᔠ=a,ZAOD=J3,ᑣD

30ᑡÏÐজmAdᙊ±〉ÔḄBd·ᑖ¯AB,ACAE,F,ᑖ¯mE,ᔆdᙊ±ᜧAØᡠḄd·ÙAH,Û2ঝᑖ¯mA,8dᙊ±ᜧAÞ48Ḅd·ÙA஻N,cMN,2ÛAOHঞm஺dᙊ±©஺4dᙊ.ூὃ௃N3-äᩖHM2ᚖᳮHKH-.{Ὺ}GḄឋ6ூI⚪௃13⚪H69yᵨூᑖ᪆௃᝞ºOAAT.[cG}GAT,ᙠRtAOCT4ᑭᵨᳮ᪀ìíîᓽV[¥¦⚪.AOA.BC,BT=TC=4,AT=y/AC2-CT2=J(2>/5)2-42=2,

31ᙠRtAOCT4ᑣᨵ=(r-2)?+42,[W/'=5,ᦑ⌱D.ூ௃!⚪ὃ#-äᩖ{Ὺ}GḄឋ6ᚖᳮ{>[⚪Ḅᐵ/ᳮ[⚪ᮣ£Nᵨᡠ¤>[¥¦⚪.2.2020öìT9,4ᑖ<᝞A88ᑁ@AO,AB=CD,Ad3஺4ZBDC=60°,ᑣ/AD8{AD

32A5øḄᙊᕜGḄBᦪ*80஺=40஺2ᦑ⌱A.ூ௃!⚪ὃ#]ᙊᕜGᳮᙊ±Gஹ·ஹüýḄᐵÁ{>P᪷TᳮAB=AD=CD[⚪Ḅᐵ/.1.2020:ᓭÿT9,3ᑖ20203ᨴ14“▭ᦪ”.⁚Ḅ᧫“ᐔDay▭ᦪᡠᙠ3ᨴ14“3.14”!ᙊᕜ᳛ᦪ%ᨬ'(Ḅᦪ).ᙠ*+,ᡠ-.Ḅᙊᕜ᳛Ḅ/01234⊝6,78ᦪ!9ᢈ;<=>Ḅ?⌕᪗B.ᡃᓭᓅF8ḄἔHIJKᨬLMᙊᕜ᳛Ḅ/0%N-ᑮPᦪQR7SḄ9TᓈVᡂX⚞ᐜIJᓟ\.]^_ᙊᕜ᳛Ḅ`⊤bcজᙊᕜ᳛ᨵᳮᦪgঝᙊᕜ᳛iᳮᦪcঞᙊᕜ᳛!ᙊḄᜧPiᐵḄmᦪno_VᙊḄᕜp!qrḄsgটᙊᕜ᳛!ᙊḄᜧPᨵᐵḄmᦪno_VᙊḄᕜp!urḄs.ᐸw⊤bx0ḄyzA.ঝঞB.জঞC.জটD.ঝটூὃQ௃1Hc(ᦪᨵᦔᦪ)g27cᦪ.ூ⚪௃511cᦪg67cᳮ.ூᑖ᪆௃᪷ᦪḄᑖᐔḄᱯQᓽ3.ᫀ.ூ௃cᙊᕜ᳛iᳮᦪ!ᙊḄᜧPiᐵḄmᦪno_VᙊḄᕜp!qrḄsᡠ⊤bx0Ḅyzঝঞgᦑ⌱cA.ூQ௃⚪ὃᦪᦪḄᑖ“ᐔ”Ḅ⚪Ḅᐵ.1.2020•ₚ¢T7•3ᑖ᝞¤஺0wOCLAB,ZAPC=28°,ᑣN8OCḄ2ᦪ

33C.42°D.56°ூὃQ௃M4cᙊ®¯ஹ±ஹ²Ḅᐵ³gM2cᚖrᳮgM5cᙊᕜ¯ᳮூ⚪௃559cᙊḄᨵᐵᭆ·¸ឋºூᑖ᪆௃᪷ᚖrᳮ3.»¼½ZAPC=28%᪷ᙊᕜ¯ᳮ3.NBOC.ூ௃cᙠ஺஺wOC.LAB,AC=BC,NAPC=28஺/.ZBOC=2ZAPC=56°,ᦑ⌱cD.ூQ௃È⚪ὃᙊᕜ¯ᳮᑭᵨᚖrᳮ.»=Ë⚪ᐵ.2.2020ÍᓭÎÏT9,4ᑖ᝞¤ᡠÑQ4ஹBஹC^ÒḄÓ2ᑖÔ0ஹ2ஹ4ஹÕÖ×C4ØQCᢥÚ8┐ÜᔣÞß7QA✌áâᙠãä3CDEḄç2EK8èQAi,ᑣ8Ö×CAêëḄ¤äḄ☢íூὃQ௃LBcãäḄឋºgMOcᡧä☢íḄN-gR2cÞßḄឋº.ூ⚪௃559cᙊḄᨵᐵᭆ·¸ឋºg66cò-.ூᑖ᪆௃óÖ×CAêëḄ¤äḄ☢íᓽóᡧä4c41Ḅ☢í.

34ூ௃cᵫ⚪÷AC=4,BC=4-2=2,ZAiBC=90°.ᵫÞßḄឋº.AiC=AC=4.1,BC1ᙠRs4BCwcos/4cAi=------=—.A,C2ZACAi=60°.ᡧäAC4Ḅ☢íᜐK¼=»7.3603QᓽÖ×CAêëḄ¤äḄ☢í2ú.3ᦑ⌱cD.ூQ௃⚪ὃᡧä☢íḄN-q¯û¯äᡧä☢íüýÈ⚪Ḅᐵ3.2020þÿT7,2ᑖ᝞஺ḄCḄCAஹ3ᔠCHLAB,ᚖM8CḄ.OḄ3,ᑣ!Ḅᨬᜧ$A.3B.4C.5D.6ூὃ௃KP()*)+,-Ḅ.ூ/⚪௃55412Ὺ*)+()*)+46715ᳮ78ூᑖ᪆௃᪷;()*)+,-.Ḅឋ=>?(ᙊᨬᜧḄᓽBCDḄᨬᜧ$3ூEF௃E1CH_LAB,ᚖ஻.".ZCMB=90°.஻8cḄ.2BCḄᨬᜧ$(Ḅ!OḄ3,

35r.MWḄᨬᜧ$3,ᦑ⌱1A.ூJ௃K⚪ὃLM()*)+,-(.Ḅឋ=NO8cḄᨬᜧ$஺Ḅ(Ḅ!E⚪ḄᐵQ.4.2020RSTUT7,3ᑖ᝞AஹBஹCᙠ஺ZACB=54°,ᑣNA6OḄWᦪA.54°B.27°C.36°D.108°ூὃ௃1ᙊY)ஹஹḄᐵZ1M51ᙊᕜ)\ᳮூ/⚪௃55412Ὺ*)+()*)+45591ᙊḄᨵᐵᭆ_?ឋ=45521*)+46715ᳮ78ூᑖ᪆௃᪷;ᙊᕜ)\ᳮC`a403,᪷;2Ὺ*)+Ḅឋ=C`a30=NB4O,᪷;*)+ᑁ)c\ᳮC`ᓽB.ூEF௃E1ZACB=54°,ᙊY)ZAOB=2ZACB=108°,OB^OA,ZABO=ZBAO=4x180஺dZAOB6=36°,ᦑ⌱1C.ூJ௃K⚪ὃLMᙊᕜ)\ᳮᙊY)ஹஹefḄᐵZ2Ὺ*)+Ḅឋ=c*)+Ḅᑁ)c\ᳮ2gh7C`ᙊY)NAOBḄWᦪEi⚪ḄᐵQ.3.2020ᵞᾓlmஹ

36o9,3ᑖ᝞AOd(AC=2,AB=4,஺ᙠ஺pqᑖ8C,ᑣDCḄ!

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