I. CÁC BỔ ĐỀ VỚI CÁC YẾU TỐ ĐẶC BIỆT CỦA TAM GIÁC:
1. 










0

0
.
2. Cho 
DEF.
,  có chu
).





.

3. 

D


 




4.2.

  



  




4.3.   
5. 
 B, C.
 






 



 
 
7.  .
  
 




8. 

g.

N
M
D
E
B
C
A
Q
P
10. 

 









.
  



 
  
 

 







 
 











  

 




các góc 





8.2. 
   
 
quy  
8.3. 
PN   
8.4. 
 AC là phân giác góc 

 
 iác góc 

 BD là phân giác góc




/ 









}
  

  A, B thì 

 


 

 4.  
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

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 N
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 
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 
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9.  
à
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 
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 
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 
a. 
b. 
c. 

 
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 g Steiner)

12. 
 
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 
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 
  
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.
 
 
13. 
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15. 
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. Ta có:
 
  
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