1、jij iJ 2022-2023 =71 0 f=!x I x 2:!j)Z x -3 l,C uA=!xi-3%:xJUll:$6.C$Ill:2Js:Jm1tliIEE19&:i!*Mffi-mBAJ11ffl,C,(I,I)!Jj,ll;jl99Jlei*1;:t.:i1,(I,I).JJJ.$2 991Jr;fj y=2x-I,_IJ!iJ a,b*r-I xtf*,it(a+b=-2.-1-7.B$l!Ullll 1fi:B1t.=:PlsiiJOOtt!ffi.NHJi ll!fil,fl:tll Pl y=2sin wx:fl y=2cos wx alfil.:!qj;,00 i
2、:j:t L:.ABC:11./iJfJ?:xt.mxtf*PJ14L:.ABC;,C:1Jf1fc!aJJll.=:1fc1%,:i:1 CJ fl:CM _1_AB TM,IJ!U AB=T=211=2BM,14 BM=.1!.,E8 sin wx=cos wx,14 w w CM 2jf jiII tanLCBA=-=-1;!;(,-JlR,EIOw:E.IV 4.w y x y=2sin wx 8.A$lffi1111 1fi:B1tJt.ffi ES/(-x)+f(x)=2cos2x,PJ1ij f(-x)-cos2(-x)+f(x)-cos2x=0.iii!:g(x)=f(x)-c
3、os2x,IJ!U g(-x)+g(x)=0,?lri;,g(x)R _taJpj,XtE(O,+oo)_tj(x)+sin 2x 0,E!P g(x)=f(x)+2sin xcos x=f(x)+sin 2x I-:1J;,b 1J.#:tEl(!.ft!MIJ:,JHJJ!0),EE B1 1 AB 89:1fli:h-:+f=1,1 CF 89:1fli:h:-t=1,w.Yjj:lf*.ll,PJM1 P 89:fi:h(2ac,(a+c)b)EE IPFI=3 IAFI,PJ1(2ac-c)2+(+c)/=9(a+c)2.a-c a-c a-c a-c 11,M:!t 70,r.MJ
4、.iizt!:lx:;:iPA,i.iEIIJltti-!JI.11.$111:zt;:Jg1lt.iEidt:fJI!fll.=:firrt!I:rfEl91iilffl.Mffi(I)EE f4PJ1(sin A-4sin Reos B)sin A=4cos Asin2 B,:fJI1 sin2 A=4sin B(sin Acos B+cos Asin B)=4sin Bsin(A+B)(2 5t)=4sin Bsin C,.(3 5t)-4-再由()可得W-EEiE5t:JE:1:!IPUl!J a2=4bc.(5%)b2+c2-a2 1(II)EE5tJE:l:i%1i cos A=2
5、bc=-2,(6%)b2+c2-4bc _ _!_-.iw:rmal_ _ _3 2bc-2 .lle:J:r.fo c+b-.(8?t)f=t,JJ!Ut+=3,E!Pt2-3t+l=O,(9:5-)3$c 3$1-!t=-2-,E!P,;s%li:tJ-2-.(10?t)18.$111:2Js:Rfil1flaJlm89f.ll:li:k*,foJ:11:*Bjf,j iiiJRfil.ffi!Hfi(I)ili!:AB Ei991Jjg O,;a CO,SO.l;Njg LABC jg11f,J.=.1f,J%,ii CA=CB=,/2,?,Jf J,V.AB=2,CO=1,ii CO
6、1-AB.(1 5t)l;Njg S tEI.V.AB jg11Ei9IE_t.,f,f J,V.SO=TAB=1.(2 5t)toe so2+co2=sc2=2,toe co 1-so.(3 5t)Jl.i:Njg ABnSO=0,toe CO 1-jl-ffii SAB,(4 5t)i;N jg CO Cf ffii ABC,Yf Id.f ffii SAB 1-f ffii ABC.(5 7t)z A y x(II)Id.0 1J*.tffiJJ1-,OC,OB YftE15tJJ1jjg x,y$dl,u,0 H1 rf ffii ABC Ef91(jg z$dl,.1L:tm i!Y
7、f 7-KEl9181jf,j*.fffi*0-xyz,JJIU A(O,-1,0),C(l,0,0),B(0,1,0).(6%)EE sinLSAB=i1t cosLSAB=f,Yfl.V.sinLSOB=sin 2LSAB=2sinLSABcosLSAB=2f,Affii1.!cosLSOB=_!_ Yfl.V.s(o _!_ 2,/2)(7 1:,.)3 33:JJ liJ.V.SA=(o _ _!_ _2,/2)SB=(o l _2,/2)BC=(l-1 o).(8%)OI 3 3 3 3 -:-x y-0 m;n-0 l-ilit-JZ-ffiiSBCEi9foJ:li1Jn=(x,y,z),JJIU.toe l _2,/2 _ (9%)SB n-0,3y 3 z-0,:!iffif,ty=,/2,JJ!U n=(,/2,/2,1).(10?t)-+-+I SA n I 2,/2/Is l;Njglcos(SA,n)I=-+=-,ISAI lnl 2./6 xJs 5 3/Is toe SA _!,;-jl-ffii SBC Yfp)tjf,JE19i5t:ffi:tJ-5-.(12%)-5-
