Bài 1: Tính
a) \(\sqrt{125}-4\sqrt{45}+3\sqrt{20}-\sqrt{80}\)
b) \(\sqrt{29^2-20^2}\)
c) \(3\sqrt{2}\left(\sqrt{50}-2\sqrt{18}+\sqrt{98}\right)\)
d) \(\sqrt{4-\sqrt{15}}-\sqrt{4+\sqrt{15}}\)
e) \(\sqrt{3-\sqrt{5}}\left(3+\sqrt{5}\right)\cdot\left(\sqrt{10}-\sqrt{2}\right)\)
f) \(2\sqrt{5}-\sqrt{125}-\sqrt{80}+\sqrt{605}\)
g) \(\sqrt{3}-3\sqrt{12}+4\sqrt{27}+3\)
Bài 2: Tìm ĐKXĐ
1) \(\sqrt{-x^2-5}\)
2) \(\frac{\sqrt{x-4}}{3}\)
3) \(\sqrt{\frac{-3}{x+1}}\)
4) \(\sqrt{\frac{-x^2-1}{x-3}}\)