tolong bantu jawab nomer 9

[tex]\frac{dx}{dt}=\cos{t}[/tex]
[tex]\frac{dy}{dt}=-2\sin{2t}[/tex]

[tex]\frac{dy}{dx}=\frac{\frac{dy}{dt}}{\frac{dx}{dt}}[/tex]
[tex]=\frac{-2\sin{2t}}{\cos{t}}[/tex]

[tex]t=\frac{\pi}{6}\rightarrow \frac{dy}{dx}=\frac{-2\sin{\frac{\pi}{3}}}{\cos{\frac{\pi}{6}}}[/tex]
[tex]\frac{dy}{dx}=-2\sqrt{3}[/tex]