Cho ∆ABC vuông tại A có AB = √3, AC = 4 và phân giác BD.

 a/ Tính BC. 

b/ Tính số đo 

c/ Chứng minh:  AB + CD : 2= BC

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căn 32 - ( căn 22 - căn 12 căn 2) - căn 4

For centuries, poets, writers and musicians have ______ (13) the ao dai in poems, novels and
songs. The ao dai is the traditional dress of Vietnamese women. It consists of a long silk tunic that is slit
on the sides and worn ______ (14) loose pants.
______ (15), it was frequently worn by both men and women. The design and ______ (16) used for men
were different from those used for women. Nowadays, women usually wear it, especially ______ (17)
special occasions. However, many Vietnamese women today often prefer to wear modern clothing at
work, because it is more ______ (18).

K2O → KOH → K2SO3 → SO2 → SO3 → Na2SO4 → NaNO3
2/ CaO → CaSO3 → SO2 → H2SO3 → K2SO3 → K2SO4 → KCl

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