Cho \(\log_ab=3;\log_ac=-2\). Biểu thức \(\log_a\left(\dfrac{a^4\sqrt[3]{b}}{c^3}\right)\) bằng
11.10.12.9.Hướng dẫn giải:\(\log_a\left(\dfrac{a^4\sqrt[3]{b}}{c^3}\right)=\log_aa^4+\log_a\sqrt[3]{b}-\log_ac^3\)
\(=4\log_aa+\dfrac{1}{3}\log_ab-3\log_ac\)
\(=4.1+\dfrac{1}{3}.3-3.\left(-2\right)\)
\(=11\)