Question

If y=lnx, find $\frac{dy}{dx}$

• A. $e^x$
• B. $\frac{1}{x}$
• C. $\frac{e}{x}$
• D. $\frac{1}{x}{e}^x$

Answer 1

The correct option is B

$\frac{1}{x}$

$\frac{d\left(lnx\right)}{dx}=\frac{1}{x}$
Table : $\frac{dy}{dx}$ for some common functions
$\begin{array}{cccc}y& \frac{dy}{dx}& y& \frac{dy}{dx}\\ x^n& n{x}^{n-1}& secx& secxtanx\\ sinx& cosx& cosecx& -cosecxcotx\\ cosx& -sinx& Inx& \frac{1}{x}\\ tanx& se{c}^{2}x& e^x& e^x\\ cotx& -cose{c}^{2}x& & \end{array}$