Question

Answer 1

a, Thay x = \(\dfrac{1}{4}\) vào A ta có

A = \(\dfrac{\sqrt{\dfrac{1}{4}+2}}{2.\dfrac{1}{4}+1}\) = \(\dfrac{5}{3}\)

 

b, B = \(\dfrac{x-\sqrt{x}-2-2\sqrt{x}-4+6+\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\) = \(\dfrac{x-2\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}\) = \(\dfrac{\sqrt{x}}{\sqrt{x}+2}\)