鯤ο
BACȤȤȡ
DEF-4
BFC4ȤȤʤΤǡ
DEF
=25*25*sin(-4)/2
=25*25*sin4/2
=25*25*24/25/2
=300
88ڡ 0:08:07 48295
٥륯åĥ
ѷţģƤģƤĤäĤƤҤţģšǣƤŤģšǤ˿򲼤Ȼѷ£ƣäȹƱʻѷǤΤǡ25242300Ȥʤޤ
ǽ2dzΤ˺600Ψ򲼤Ƥޤޤ

ѤˤĤƽ񤤤ƤʤäΤɵ
ѣ1ȤջѷȳѤdzѣţģơѣţƣġ2ѣ£ƣá4ȤʤΤǹƱʤΤʬޤ
88ڡ 0:29:16 48296
Mr.ǥ
鯤οͤ(#48295
BACȤȤơBFC4ȡDF=EFD=2
BFCʬBCθGȤ
CFG=2
BG:CG=25:7
CG=24x(7/32)=21/4
FC:CG=7:(21/4)=4:3
FCGϡ345ľѻѷ

EDFˤ­HȤ
EFHᢤEDH345λѷȤʤ
DH=FH=20,EH=15
EFD=(1/2)x40x15=300
ǻϰϤʡ
88ڡ 0:22:06 48297
Ȥ
DF=2*a,E򲼤­GȤ
AEG梤ABC
EG:(=sqrt(25^2-a^2)):BC(=24)=AG(=25+a):AC(=32+2*a)
24*(25+a)=(32+2*a)*sqrt(25^2-a^2) ξ2Ǥ
24^2*(25+a)^2=(32+2*a)^2*(25^2-a^2)
򤤤a*sqrt(25^2-a^2)Ǥ롡XMaxima

ev(a*sqrt(25^2-a^2),part(solve(24^2*(25+a)^2=(32+2*a)^2*(25^2-a^2),a),2));300()
˭ԡ 88ڡ 0:54:23 48298
ǯ
A˷׻Ƥ椯ȡ2EDF2EFDBFC
EDFľ˿ȾʬڤäơDF碌ơѷȡ
ĺѤBCFƱǡդ25ջѷˤʤ롣
ջѷ򡢭BCFӤȡ25⤵24λѷǤ⤢뤳Ȥ狼롣
ΤˡѤ25*24/2=300

89ʶ 16:32:36 48299
鯤ο
٥륯åĥƱǤDEαĹFFG򲼤ȡFEGᢤBFCȤʤΤѤΤ򤫤ʡ
ϰϤDz򤳤Ȥȡġγ٤ϵʤ顢BFCȹƱޤο޷õor뤷ʤȡȯۤǤС®ǤΤ⡣
Mr.ǥ3:4:5ȯ⡢μȤΤäƤ顢׻ˡȤꤢѥäȸǡ֥Ǥ⡣

88ڡ 0:59:33 48300
ֿء׾ι
桢ȤäƤޤޤɤΤʤ
88ڡ 1:24:09 48301
Ȥ
βˡɸǤʤäΤǡ

ɸ
A(-32-2*a,0),B(0,24),C(0,0),D(-7-2*a,0)
E(-25-a,sqrt(25^2-a^2)),F(-7,0)Ȥ
ľEF:y=-sqrt(25^2-a^2)*(x+7)/ax=0Ȥ
G(0,-7*sqrt(25^2-a^2)/a)
ǢEFCB=EGB(=(GB(=7*sqrt(25^2-a^2)/a)+CB(=24))*(7+a)/2)-GFC(=GC*FC/2=7^2*sqrt(25^2-a^2)/(2*a))
=7*sqrt(625-a^2)/2+12*a+84(1)
ǢACB(=(32+2*a)*12)
=ADE(=25*sqrt(25^2-a^2)/2)+DEF(=a*sqrt(25^2-a^2))-EFCB(=7*sqrt(25^2-a^2)/2+12*a+84)
(32+2*a)*12=25*sqrt(25^2-a^2)/2+a*sqrt(25^2-a^2)+7*sqrt(25^2-a^2)/2+12*a+84 ѷ
12*a+300=(a+16)*sqrt(25^2-a^2) ξ2褷ƺդ鱦դ
(12*a+300)^2-(a+16)^2*(25^2-a^2)
=a^4+32*a^3-225*a^2-12800*a-70000=(a-20)*(a+7)*(a+20)*(a+25)=0
aʤΤa=20
DEF=a*sqrt(25^2-a^2)
DEF=20*sqrt(25^2-20^2)=20*sqrt(225)=20*15=300()
˭ԡ 88ڡ 2:32:22 48302
cocogoo
BAC=Ȥ롣ꡢBFC=4ѷEDF=25cos2 x 2 x 25➗2

= 625 x 1/2 sin4 = 625 x 1/2 x 24/25 = 300
88ڡ 6:47:18 48303

ǡ⤦դ30cmˤʤ뤫顢345λѷĤǤ櫓
εդꡡ 88ڡ 11:07:27 48304
Ȥ
BAC=aǤʤDEF=2*aǤäƤߤޤ!!

DEF=2*a(1)Ȥ
EDF=(180-2*a)/2=90-a=EFD(ED=EF)(2)
AED=45-a/2 (1)Ȥ
BEF=180-AED(=45-a/2)-DEF(=2*a)=180-(45-a/2)-2*a=135-3*a/2
EFB=180-2*(135-3*a/2)=-90+3*a(2)Ȥ
BFC=180-EFB(=-90+3*a)-EFD(=90-a)=180+90-3*a-90+a=180-2*a
sin(BFC)=sin(180-2*a)=sin(2*a)=24/25
(1)颤DEF=25^2*sin(2*a)/2
DEF=25^2*(24/25)/2=25*24/2=25*12=300()
˭ԡ 88ڡ 11:11:22 MAIL:fttnm528@ybb.ne.jp 48305
Ȥ
ߤޤ٤ˡ4ܤǤޤ
ɸ2ˡܤǤa=20Ǥʤa=15ǤƤƤƤ
Ǥޤ!!

ɸA(0,0),B(b,0),DF=2*aȤ
A,B濴ˤ줾Ĺ25+2*a,25αߤθȤ
F᤹ľAFޤꡦ(1)
ľA濴Ĺ25αߤθȤD
xɸ2ܤExɸǤyɸ0
Ⱥǽ˵᤿FεΥ25
ʿbˤĤƲ(1)ľB̤
ľ˸ľBCȤθʬBC=24Ȥ
aΰѿǤƤDF=2*aޤ
EDFѤޤ롡XMaxima

part(solve([x^2+y^2=(25+2*a)^2,(x-b)^2+y^2=25^2],[x,y]),1)$
part(solve([y=rhs(part(%,2))*x/rhs(part(%,1)),x^2+y^2=25^2],[x,y]),1)$
part(solve(part(-num(factor((2*rhs(part(%o2,1))-rhs(part(%o1,1)))^2+rhs(part(%o1,2))^2-25^2)),4),b),2)$
factor(ev(rhs(part(%o1,1)),%o3))$
factor(ev(rhs(part(%o1,2)),%o3))$
ev(%,abs(a)=a)$
part(solve([y=%o6*x/%o4,y=-%o4*(x-rhs(%o3))/%o6],[x,y]),1)$
factor((rhs(%o3)-rhs(part(%o7,1)))^2+rhs(part(%o7,2))^2-24^2)$
ev(a*sqrt(25^2-a^2),part(solve(-num(%o8),a),4));300()
˭ԡ 88ڡ 18:08:08 MAIL:fttnm528@ybb.ne.jp 48306
ˤ
դ򺸤˱Фʻѷޤ
88ڡ 18:40:26 48307
ˤ
Ǥ
88ڡ 18:41:02 48308
leaf
ѤǤ겡ޤऺ
89ʶ 0:57:31 48310
ˤ⡼
DEFߤ˹ƱʣľѻѷĤǤǤƤ뤳ȤʬϽФΤǤϰϤǤβפ⤫ӤޤǤ

ٵ̣ǣ³Ƥؤ餺Ʊνȥơ1kgĩ魯ˤ⡼
¡ 89ʶ 1:50:20 HomePage:ͥĤäƤߤ48311
Ѥ
ȤƤ⤦㤰㡣ǧߤǤȤۤۡ
89ʶ 9:14:40 48312

پcadǿ̰ޤ
ܤʲˡϤʤʤ񤷤Ǥ
89ʶ 12:05:25 48313
å
ACޤ֤ơEDEǤ˿򲼤ȡBFCȹƱʻѷˤʤޤ͡

810ڡ 5:17:36 48314
Ҥ
sin5A=24/25,S=(1/2)*25*25*sin(180-5A)=300
810ڡ 14:09:21 48315
Ҥ
>48315
5A
4A
810ڡ 14:15:43 48316
⡼ޥ
ä¸ߤޤ

褯狼ʤäΤǤ...
ACޤ֤EDE'ؤοE'EFؤοĹƱˤʤꡢFE'=FBBE'EFľ򤷤ޤ͡
Ȥʤ...BAC=ȤȤȤBFC=4ȤȤʤꡢ10=180
BFC=72ȤʤȻפΤǤ...ΤȤBFC25-7-24ȤϤʤޤ...?

ɤΤʤ ^^;
810ڡ 14:22:08 48317

>>48317
ɤγѤ­10=180μˤΤȡ
̵ռˢBAC=FBCȤꤷƤʤǤ礦
810ڡ 23:05:05 48318
⡼ޥ
­Ѥ...
EFE'=4=EFB=4
BFC=4
..EFD(2)+EFB(4)+BFC(4)=10=180
ˤʤʤΤ...^^;
810ڡ 23:22:59 48319



> ACޤ֤EDE'ؤοE'EFؤοĹƱˤʤꡢFE'=FB
ޤǤϴְäƤʤɡ
> BE'EFľ򤷤ޤ͡
Ȥϸʤ
810ڡ 23:44:08 48320
٥륯åĥ
ʤFE'=FBBE'EFľȤʤΤǤ礦
ѣţƣšǡѣţƣ¤ǤϤޤ͡
810ڡ 23:56:19 48321
⡼ޥ
͡٥륯å
ä ^^;
ջѷFE'BˤơE'EFؤο,EFBE'Ȥľ򤹤Ȥ˰դ˷ޤȻפäƤޤ...
ʬδְäפߤǤޤ
ޤͤ͡ʤm(_ _)m

ξ꤬͡Ȥޤ Orz
811 10:21:52 48322
⡼ޥ
٥륯åĥ
Ȥʤ
ְ㤨Ƥޤޤ
ǽȤǤͤӿ夲ޤm(_ _)m
811 10:26:19 48324
⡼ޥ
Orz...
٤⤹ߤޤ ^^;;
ؤ٢ؤ̾
811 10:29:16 48325

ޤǻ鯤οͤƱ
BACȤȤȡ
DEF-4
BFC4ȤȤʤΤǡ
BFA=-4
ĤޤꡢDEF=BFA
ʤΤAFFG=25ȤʤGȤȢDEFᢤBFG
25⤵24λѷǤ뤫Ѥ300
811 11:04:15 48326
٥륯åĥ
䥹⡼ޥ󤵤󡢤
ߤޤ󡢴ˤƱȤ񤫤Ƥ褦ǡ;פʽ񤭹ߤä⤷ޤ
פߤˤ봪㤤Ϥ꤬Ǥ͡褯ΤǡʤȤϤ˽񤭹¾οͤλŦ˴Ԥꤷޤ
811 12:40:53 48327
⡼ޥ
٥륯åĥ
ͥդ˴դǤm(_ _)m
줫Ĩꤺˤ⤷ʤ錄Ǥ ^^;...
811 23:57:58 48328