Đưa thừa số vào trong dấu căn: a) \(4\sqrt 3 ;\) b) \( - 2\sqrt 7 ;\) c) \(4\sqrt {\frac{{15}}{2}} ;\) d) \( - 5\sqrt {\frac{{16}}{5}} .\)

a) \(4\sqrt 3 = \sqrt {{4^2}.3} = \sqrt {16.3} = \sqrt {48} .\)

b) \( - 2\sqrt 7 = - \sqrt {{2^2}.7} = - \sqrt {4.7} = - \sqrt {28} .\)

c) \(4\sqrt {\frac{{15}}{2}} = \sqrt {{4^2}.\frac{{15}}{2}} = \sqrt {16.\frac{{15}}{2}} = \sqrt {120} .\)

d) \[ - 5\sqrt {\frac{{16}}{5}} = - \sqrt {{5^2}.\frac{{16}}{5}} = - \sqrt {25.\frac{{16}}{5}} = - \sqrt {80} .\]