Question

Answer 1

Bài 4a; 

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

 

Answer 2

b; 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 = 2.\(\dfrac{7}{3}\)

   B = \(\dfrac{14}{3}\) 

Answer 3

              Bài 5a;  

A = (20\(\sqrt{300}\) - 15\(\sqrt{675}\) + 5\(\sqrt{75}\)) : \(\sqrt{15}\)

A =  (20.\(\sqrt{100.3}\) - 15.\(\sqrt{225.3}\) + 5.\(\sqrt{25.3}\)) : \(\sqrt{15}\)

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

Answer 4

           Bài 5b; 

B = (\(\sqrt{325}\) - \(\sqrt{117}\) + 2\(\sqrt{208}\)) : \(\sqrt{13}\)

B = (\(\sqrt{25.13}\) - \(\sqrt{9.13}\) + 2\(\sqrt{16.13}\)): \(\sqrt{13}\)

B = (5\(\sqrt{13}\) - 3\(\sqrt{13}\) + 2.4\(\sqrt{13}\)) : \(\sqrt{13}\)

B = (2\(\sqrt{13}\) + 8\(\sqrt{13}\)): \(\sqrt{13}\)

B = 10\(\sqrt{13}\) : \(\sqrt{13}\)

B =  10