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BD

*> [BD] jM& l̂ feU j« Unii M

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BM MD— =—

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BC = 8>/2 3 AB = AC = 8 £*>• lilio ABC j£J -1

A .̂gà ^3'j" f^l* ABC u^Jt** !̂ b^ O^

BF = x j^îCJ 3 B 3 A J &îbw [ AB] ̂ F 4tûj j*a« -2

gj (BC) <jfcwi (AB) ̂ 4.5̂ 3*̂ 13 F O* JW' (0*&^«Jt

^if -in-n '. \

= X Ù* 0*̂ "

g= x ( 8 x )AEF

8 J AEF

[AB]

0 < a < 8

x

F 5JbflUf 9̂3* <3Jbs)f eJJb

3ULJLJ! oJ

* 60

2 / 2

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[80 ; 100[

20

[60 ; 80[

60

[40 ; 60[

210

[20 ; 40[

490

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220

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A£ A du (PGCD(2,7) = \)

.J-"''"'•" J& 4jaSJffl

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\fl.iill , "jjjollj -^A **-.-*>* -^l*Wl J | 2012 ùL^

b = 7 + 4^/3 ja = 7-4^/3 :ùàAb jj>Jlt-jJL» eA a

a b 2 , 2-+ — = a2 + bb a 7- W3) = (7)2 - (4V3)

= 97 + 56VJ+ 97 - 56

= 4^-16x3 = 49-48 =j cr il,

42 x 7x +

16^3 = 97+ 56^3

= (7)2-2x7,,x

= 49-56^3+ 16* 3 = 97- 56^3X ..^..v

. /BM = <

MD = Jîî JBD = 5^/2 J M e [BD]

BM = BD- MD BD = BM + MD :ûiBM = 5V2 - VÊ = 5 V2 -

BM MD BM + MD

MD = «Je JBM = JÏ8BM MD . .

MD = -BD JBM -5

5 Jj [BD] f 3 2

BM JÎ8[BD 1 Û* M

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A ̂ Ljljlt ffâ ABCBC2 = (8>/2)2 =82x(V2)2 =64x2 = 128

ABC LÎJÎiJlC' LjJJ

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AC = 8

(AC)I/(EF)û4'(AB)±ÏAty j (AB) 1

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BE EK BF BE EFBA = 8

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BC ACx EF

^J FBE = 45° <*j ABC * ACB = 45° fyA J j= EBF = 45° ^Jpf990° - EBF = 90°- 45° -45° ù

EF = x F

a = EFxFA

\ EF- x

/ « _i O C* — O

: J& (1.3_ 42-2x4xx + x2 = (4-x)2

2 2 20 < a < 8 ÙÎ&&*} (V

F • • l J Fe[AB]j B F = - B A <^J

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JÏ l-«-''-«l

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= 220+490+210+60+20=1000

[80,100[

20

90

[60,80[

60

70

[40,60[

210

50

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490

30

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220x10 + 490x30 + 210x50 + 210x5 d*V6 0 x 70\+ 20 x90.

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10 20 M(3CL 31 34 40

220 + 490 + 2 1 0 .J .3

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