Bài 4a; A = \(\sqrt{1,6}\).\(\sqrt{250}\) + \(\sqrt{19,6}\): \(\sqrt{4,9}\)
A = \(\sqrt{1,6.250}\) + \(\sqrt{19,6:4,9}\)
A = \(\sqrt{400}\) + \(\sqrt{4}\)
A = \(\sqrt{20^2}\) + \(\sqrt{2^2}\)
A = 20 + 2
A = 22
B = \(\sqrt{1\dfrac{3}{4}.2\dfrac{2}{7}.5\dfrac{4}{9}}\)
B = \(\sqrt{\dfrac{7}{4}.\dfrac{16}{7}.\dfrac{49}{9}}\)
B = \(\sqrt{4.\dfrac{49}{9}}\)
B = \(\sqrt{\left(4.\dfrac{7}{3}\right)^2}\)
B = 2.\(\dfrac{7}{3}\)
B = \(\dfrac{14}{3}\)
Bài 5:
a; A = (20\(\sqrt{300}\) - 15\(\sqrt{675}\) + 5\(\sqrt{75}\)):\(\sqrt{15}\)
A = (20\(\sqrt{10^2.3}\) - 15.\(\sqrt{15^2.3}\) + 5.\(\sqrt{5^2.3}\)) : \(\sqrt{15}\)
A = (20.10\(\sqrt{3}\) - 15.15\(\sqrt{3}\) + 5.5.\(\sqrt{3}\)):\(\sqrt{15}\)
A = (200\(\sqrt{3}\) - 225\(\sqrt{3}\) + 25\(\sqrt{3}\)) : \(\sqrt{15}\)
A = (-25\(\sqrt{3}\) + 25\(\sqrt{3}\)) : \(\sqrt{15}\)
A = 0 : \(\sqrt{15}\)
A = 0
Bài 5b;
B = (\(\sqrt{325}\) - \(\sqrt{117}\) + 2\(\sqrt{208}\)) : \(\sqrt{13}\)
B = (\(\sqrt{5^2.13}\) - \(\sqrt{3^2.13}\) + 2\(\sqrt{4^2.13}\)): \(\sqrt{13}\)
B = (5\(\sqrt{13}\) - 3\(\sqrt{13}\) + 2.4\(\sqrt{13}\)): \(\sqrt{13}\)
B = (5\(\sqrt{13}\) - 3\(\sqrt{13}\) + 8\(\sqrt{13}\)) : \(\sqrt{13}\)
B = \(\sqrt{13}\).(5 - 3 + 8) ⋮ \(\sqrt{13}\)
B = \(\sqrt{13}\).(2 + 8):\(\sqrt{13}\)
B = (\(\sqrt{13}\) : \(\sqrt{13}\)).(2 + 8)
A = 1.10
A = 10
