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Question: Lim x tends to 2024 (sinx-sin2024) /(cosx-cos2024)...

Lim x tends to 2024 (sinx-sin2024) /(cosx-cos2024)

Answer

-cot(2024)

Explanation

Solution

The limit is of the form 00\frac{0}{0} as x2024x \to 2024. Using trigonometric identities sinxsina=2cos(x+a2)sin(xa2)\sin x - \sin a = 2 \cos\left(\frac{x+a}{2}\right) \sin\left(\frac{x-a}{2}\right) and cosxcosa=2sin(x+a2)sin(xa2)\cos x - \cos a = -2 \sin\left(\frac{x+a}{2}\right) \sin\left(\frac{x-a}{2}\right), the expression simplifies to cot(x+a2)-\cot\left(\frac{x+a}{2}\right) for xax \neq a. Taking the limit as xa=2024x \to a=2024, we get cot(a+a2)=cot(a)=cot(2024)-\cot\left(\frac{a+a}{2}\right) = -\cot(a) = -\cot(2024). Alternatively, applying L'Hopital's rule, the limit is limx2024ddx(sinxsin2024)ddx(cosxcos2024)=limx2024cosxsinx=cos2024sin2024=cot2024\lim_{x \to 2024} \frac{\frac{d}{dx}(\sin x - \sin 2024)}{\frac{d}{dx}(\cos x - \cos 2024)} = \lim_{x \to 2024} \frac{\cos x}{-\sin x} = \frac{\cos 2024}{-\sin 2024} = -\cot 2024.