a) \(\sqrt{a^3\left(a-1\right)^2}\)
\(=\sqrt{\left(a\left(a-1\right)\right)^2.a}\)
\(=a\left(a-1\right).\sqrt{a}\)
\(=a\sqrt{a}\left(a-1\right)\) (Vì a≥1)
b) \(\sqrt{75}+\sqrt{48}-\sqrt{300}\)
\(=5\sqrt{3}+4\sqrt{3}-10\sqrt{3}\)
\(=\left(5+4-10\right)\sqrt{3}\)
\(=-1.\sqrt{3}\)
\(=-\sqrt{3}\)
a)
\(=\sqrt{a^3}.\sqrt{\left(a-1\right)^2}=\sqrt{a^3}.\left(a-1\right)\) với a >_1
b)
\(=5\sqrt{3}+3\sqrt{5}-10\sqrt{3}=3\sqrt{5}-5\sqrt{3}\)
c)
\(=7\sqrt{2}-6\sqrt{2}+\sqrt{2}=2\sqrt{2}\)
d)\(=-5\sqrt{3a}+27\) \(\left(a\ge0\right)\)
e)
\(=3\sqrt{2a}-10\sqrt{2a}+21\sqrt{2a}+28
\left(a\ge0\right)\)
\(=14\sqrt{2a}+28\)
