If $y=e^{\frac{1}{2}\log_et}$ and $x=\log_3(e^{t^2})$, then $\frac{dy}{dx}$ is equal to:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $\frac{\log_e3}{4t\sqrt{t}}$
$y=e^{\frac{1}{2}\log_et}$
$⇒y=t^{\frac{1}{2}}=\sqrt{t}$ $(∵e^{\log_ea})$
$⇒\frac{dy}{dt}=\frac{1}{2}t^{-\frac{1}{2}}=\frac{1}{2\sqrt{t}}$ ...(1)
Now,
$x=\log_3(e^{t^2})$
$x=t^2\log_3e$ $(∵\log_ab^c=c\log_ab)$
$x=\frac{t^2}{\log_e3}$ $\left(∵\log_e3=\frac{1}{\log_e3}\right)$
$⇒\frac{dx}{dt}=\frac{2t}{\log_e3}$ ...(2)
From (1) & (2)
$\frac{dy}{dx}=\frac{\frac{1}{2\sqrt{t}}}{\frac{2t}{\log_e3}}=\frac{1}{2\sqrt{t}}×\frac{\log_e3}{2t}=\frac{\log_e3}{4t\sqrt{t}}$