Question

Tính giá trị biểu thức sau:

a) A = \(\frac{{2\cos {{45}^o}}}{{\sqrt 2 }} + \sqrt 3 \tan {30^o}\)

b) B = \(\frac{{2\sin {{60}^o}}}{{\sqrt 3 }} - \cot {45^o}\) 

Answer 1

a) A = \(\frac{{2\cos {{45}^o}}}{{\sqrt 2 }} + \sqrt 3 \tan {30^o} = \frac{{2.\frac{{\sqrt 2 }}{2}}}{{\sqrt 2 }} + \sqrt 3 .\frac{{\sqrt 3 }}{3} = 1 + 1 = 2\)

b) B = \(\frac{{2\sin {{60}^o}}}{{\sqrt 3 }} - \cot {45^o} = \frac{{2.\frac{{\sqrt 3 }}{2}}}{{\sqrt 3 }} - 1 =  1- 1 =  0\).