c) \(2\sqrt{\dfrac{16}{3}}-3\sqrt{\dfrac{1}{27}}-6\sqrt{\dfrac{4}{75}}\)

a) \(\dfrac{10+2\sqrt{10}}{\sqrt{5}+\sqrt{2}}+\dfrac{8}{1-\sqrt{5}}\)

Chứng minh đẳng thức:

a) \(\dfrac{\sqrt{a}}{\sqrt{a}-\sqrt{b}}-\dfrac{\sqrt{a}}{\sqrt{a}+\sqrt{b}}-\dfrac{2b}{a-b}=\dfrac{2\sqrt{b}}{\sqrt{a}+\sqrt{b}}\)

( với a > hoặc bằng 0; b > hoặc bằng 0; a khác b )

d) \(x-5\sqrt{x}+6=0\)

e) \(\sqrt{x-1}+\dfrac{3}{2}\sqrt{4x-4}-\dfrac{2}{5}\sqrt{25x-25}=4\)

f) \(\sqrt{x-5}+\sqrt{4x-20}-\dfrac{1}{3}\sqrt{9x-45}=6\)

a) \(\sqrt{2x-5}=2\)

b) \(\sqrt{x^2-6x+9}=7\)

c) \(\sqrt{x^2-8x+16}=4-x\)

\(E=\left(2\sqrt{6}-4\sqrt{3}+5\sqrt{2}-\dfrac{1}{4}\sqrt{8}\right)\)\(.3\sqrt{6}\)

\(D=\dfrac{2}{\sqrt{3}-1}-\dfrac{1}{\sqrt{3}-2}+\dfrac{12}{\sqrt{3}+3}\)

\(C=\sqrt{\left(5-\sqrt{3}\right)^2}+\sqrt{7-4\sqrt{3}}\)

\(B=4\sqrt{12}+\sqrt{108}-8\sqrt{3}+\sqrt{7-4\sqrt{3}}\)