Ta có: \(5a\sqrt{64ab^3}-\sqrt{3}.\sqrt{12a^3b^3}-5b\sqrt{81a^3b}\)
\(=5a.8b.\sqrt{ab}-\sqrt{3}.2\sqrt{3}.ab.\sqrt{ab}-5b.9a\sqrt{ab}\)
\(=40ab.\sqrt{ab}-6ab.\sqrt{ab}-45ab.\sqrt{ab}\)
\(=40ab.\sqrt{ab}-6ab.\sqrt{ab}-45ab.\sqrt{ab}\)
\(=-11ab\sqrt{ab}\)
\(5a\sqrt{64ab^3}\) \(-\sqrt{3}\)\(.\sqrt{12a^3b^3}\)\(-5b\sqrt{81a^3b}\)
\(=40ab\sqrt{ab}\)\(-6ab\sqrt{ab}-45ab\sqrt{ab}\)
\(=\left(40ab-6ab-45ab\right)\sqrt{ab}\)
\(=-11ab\sqrt{ab}\)
\(=5a\sqrt{64b^2\left(ab\right)}-\sqrt{3\cdot12a^2b^2\left(ab\right)}-5b\sqrt{81a^2\left(ab\right)}\)
\(=5a\cdot8b\sqrt{ab}-\sqrt{36a^2b^2\left(ab\right)}-5b\cdot9a\sqrt{ab}\)
\(=40ab\sqrt{ab}-6ab\sqrt{ab}-45ab\sqrt{ab}\)
\(=-11ab\sqrt{ab}\)
