Google
Câu hỏi: Với $a,b$ là các số thực dương bất kì, $\text{lo}{{\text{g}}_{2}}\dfrac{a}{{{b}^{2}}}$ bằng:
A. $\dfrac{1}{2}\text{lo}{{\text{g}}_{2}}\dfrac{a}{b}$.
B. $\text{lo}{{\text{g}}_{2}}a-\text{lo}{{\text{g}}_{2}}\left( 2b \right)$.
C. $2\text{lo}{{\text{g}}_{2}}\dfrac{a}{b}$.
D. $\text{lo}{{\text{g}}_{2}}a-2\text{lo}{{\text{g}}_{2}}b$.
A. $\dfrac{1}{2}\text{lo}{{\text{g}}_{2}}\dfrac{a}{b}$.
B. $\text{lo}{{\text{g}}_{2}}a-\text{lo}{{\text{g}}_{2}}\left( 2b \right)$.
C. $2\text{lo}{{\text{g}}_{2}}\dfrac{a}{b}$.
D. $\text{lo}{{\text{g}}_{2}}a-2\text{lo}{{\text{g}}_{2}}b$.
$\text{lo}{{\text{g}}_{2}}\dfrac{a}{{{b}^{2}}}=\text{lo}{{\text{g}}_{2}}a-2\text{lo}{{\text{g}}_{2}}\left( b \right)$
Đáp án D.