Bài 1: Tính
a) \(\left(\sqrt{x}-\sqrt{y}\right).\left(\sqrt{x}+\sqrt{y}\right)\)
b) \(\left(\sqrt{x}-3\right).\left(\sqrt{x}+2\right)\)
c) \(\sqrt{\left(2-\sqrt{5}\right)^2.\left(2+\sqrt{5}\right)^2}\)
d) \(\sqrt{\left(-5\right)^2.3^2}\)
e) \(\sqrt{\frac{5}{27}.\frac{8}{20}}\)
Bài 2: Tính
a) \(\left(\sqrt{14}+\sqrt{6}\right).\sqrt{5-\sqrt{27}}\)
b) \(\sqrt{4+\sqrt{5\sqrt{3}+5\sqrt{48-10\sqrt{7+4\sqrt{3}}}}}\)
c) \(\sqrt{5-\sqrt{3-\sqrt{29-12\sqrt{5}}}}\)