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Câu hỏi: Cho $a,b>0, {{\log }_{3}}a=p, {{\log }_{3}}b=p$. Mệnh đề nào dưới đây đúng?
A. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r+p.m-q.d$
B. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r+p.m+q.d$
C. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r-p.m-q.d$
D. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r-p.m+q.d$
A. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r+p.m-q.d$
B. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r+p.m+q.d$
C. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r-p.m-q.d$
D. ${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)=r-p.m+q.d$
${{\log }_{3}}\left( \dfrac{{{3}^{r}}}{{{a}^{m}}{{b}^{d}}} \right)={{\log }_{3}}{{3}^{r}}-{{\log }_{3}}\left( {{a}^{m}}{{b}^{d}} \right)=r-{{\log }_{3}}{{a}^{m}}-{{\log }_{3}}{{b}^{d}}=r-m{{\log }_{3}}a-d{{\log }_{3}}b$
Đáp án C.