Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Numbers, Quantification and Numerical Applications

Question:

If $y=log_3 (log_3x), $ then $\frac{dy}{dx}=$

Options:

$\frac{1}{xlog3x}$

$\frac{1}{x(xlog3+logx)}$

$\frac{logx}{xlog3}$

$\frac{1}{xlogx\, log 3}$

Correct Answer:

$\frac{1}{xlogx\, log 3}$

Explanation:

The correct answer is Option (4) → $\frac{1}{xlogx\, log 3}$

$y=\log_3(\log_5x)$

$=\frac{ln(\log_3x)}{ln\,3}$

$⇒\frac{dy}{dx}=\frac{1}{ln\,3}\frac{d}{dx}[ln(\log_3x)]$

$=\frac{1}{ln\,3\log_3x.x}$