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曲阜师范大学附中273165李凤华ABCDa,Rr.图11,ABCDOB,C,D,OBCDO1B,C,D.ABCDvBCD,O1vBCD,ABCD,AO1LBCD,OAO1;:O.ABCD,,OA=OB=OC=OD,:O,OABCD.,.ABCDh,r+R=h=63a.,rR,.图21()2,ABCD,vBCD,O1,O1D=33a.OO1LBCD,O1DBCD,OO1LO1D.,RtvOO1D,,OD2=OO21+O1D2,R2=63a-R2+33a21R=64a,r=63a-R=612a.64a612a.图32()3,DOABCG,GvABC.DO1BCE,A,G,E,EO1ED=13=EGEA;GO1,GO1MAD,O1OAO=O1GAD=EGEA=13,AO=34AO1=64a,OO1=14AO1=612a164a612a1:,1B2;,1B3.图43()4,ABCDV,S,h,O,OA,OB,OC,OD,V=VOABC+VOBCD+VOCDA+VODAB,13Sh=4#13Sr,r=14h=612a,R=34h=64a164a612a1:1.V,S,,r=3VS;2.h,Sh.4(),.,.x,2R=3xa=2x,R=64a,r=13R=612a.64a612a1:,,12x=24a,,24a.30ZHONGXUESHUXUEZHAZHI20081/10/Aa+x+Bb-x0北京建工学院100044中央民大附中100081/y=Aa+x+Bb-x0,/10,/101=(a+x)+(b-x)a+b,:y=1#Aa+x+Bb-x=(a+x)+(b-x)a+b#Aa+x+Bb-x=1a+bA+B+A(b-x)a+x+B(a+x)b-x\1a+b(A+B+2AB)=(A+B)2a+b:1y=4cos2x+9sin2x1=cos2x+sin2x/10y=1#4cos2x+9sin2x=(cos2x+sin2x)4cos2x+9sin2x=13+4tan2x+9cot2x\13+2#2tanx#3cotx=2525,4tan2x=9cot2x.tan2x=3212y=Aa+bx+Bc-dx(a,b,c,d,A,BIR+,0xcd)b,d,,/10:1.,,a,b,c,12a2+b2+c2;2.Pa,b,c,O,PO=a2+b2+c2;3.POm,n,lx,y,z,PO=2(x2+y2+z2)2.(23.)5()5,,A(0,0,63a)B(0,-33a,0)C(12a,36a,0)D(-12a,36a,0)O(x,y,z),图5|OA|=|OB|=|OC|=|OD|=R,|OA|2=|OB|2=|OC|2=|OD|2,x2+y2+(z-63a)2=x2+(y+33a)2+z2=(x-12a)2+(y-36a)2+z2=(x+12a)2+(y-36a)2+z21x=y=0,z=612a.r=z=612a,R=64a.64a612a15,,,.3120081ZHONGXUESHUXUEZHAZHI