Question

Answer 1

Câu 33:

\(=\sin27,5^0-\sin27,5^0+\dfrac{\sqrt{3}}{2}=\dfrac{\sqrt{3}}{2}\)

Answer 2

Câu 28:

Áp dụng HTL vào ΔABC ta có: 

\(BH.BC=AB^2\Rightarrow BC=\dfrac{3^2}{2}\Rightarrow BC=\dfrac{9}{2}\)

\(BH+CH=BC\Rightarrow CH=\dfrac{9}{2}-2\Rightarrow CH=\dfrac{5}{2}\)