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Trang 5DAp AN DE THr nnON roAN Lop 9 noc rY r NAvr Hoc 2017-2019
I rnAc NGHTpM: 1+ aiom;
U6i cau ching 0,25 cli6m
Bdi 1
Bdi2
a Truc c[n thric O thric sau:
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D6 thinhu hinh vE
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phuong trinh dudng th5ng {d} ta du-o c
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0,5 d
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Trang 6Bai 3
Bei 4
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Do AC, BD, CD ld c6c tiiSp tuyiSn cria duong trdn (O,R)'
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oS ld phdn gi6c cfia g6c S-F,{E - 5= : Fi
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Hay tam gi6c {"08 vuOng t1i O
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Tam gi6c OCD vu6ng t1i O ta dugc
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X6t tam gi6c w6ng dEE
dE I*r:.HEE :;E
.AE
tan45L- :;
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X6t tam gi6c CEfr vu6ng tai S
.CJID
tan3Du :
DE- DE: t=o308
frE :f : ,* tr:{''4
-,{D : BE -,*E = 7*{}': - 1}(r"}
DiQn tich thfta ruQng ld
S: AB.Ail =:s.rr{\iT-1} :+scs{}iT- r}tmr)
ndy qua bdi kl6c.