If $x = e^{\cos 2t}, y = e^{\sin 2t}$, then $\frac{dy}{dx}$ equals to |
$\frac{y\log_ex}{x\log_ey}$ $\frac{x\log_ex}{y\log_ey}$ $-\frac{y\log_ex}{x\log_ey}$ $\frac{-x\log_ex}{y\log_ey}$ |
$-\frac{y\log_ex}{x\log_ey}$ |
The correct answer is Option (3) → $-\frac{y\log_ex}{x\log_ey}$ Given: \(y = e^{\sin 2t}\) \(\Rightarrow \ln y = \sin 2t\) Also, \[ \frac{dy}{dx} = - e^{\sin 2t - \cos 2t} \cdot \cot 2t = - \frac{e^{\sin 2t}}{e^{\cos 2t}} \cdot \cot 2t = - \frac{y}{e^{\cos 2t}} \cdot \cot 2t \] From \(x = e^{\cos 2t}\), \(\ln x = \cos 2t\) So, \[ \frac{dy}{dx} = - \frac{y}{x} \cdot \cot 2t \] Express \(\cot 2t\) in terms of \(\sin 2t = \ln y\) and \(\cos 2t = \ln x\): \[ \cot 2t = \frac{\cos 2t}{\sin 2t} = \frac{\ln x}{\ln y} \] Therefore, \({\frac{dy}{dx} = - \frac{y}{x} \cdot \frac{\ln x}{\ln y}}\) |