$\lim_{x\to 0}\frac{(\sin{4x})(-\cos{x})}{x}$ without l'Hôpital's Rule?

148 Views Asked by At

I've thought of the sandwich theorem but can't find anything to squeeze it in !

1

There are 1 best solutions below

1
On BEST ANSWER

Let's build our way up to the answer.

Step 1. Find the value of $$\lim_{x\to 0} \frac{\sin 4x}{4x}$$

Step 2. Use the result above to find the value of $$\lim_{x\to 0} \frac{\sin 4x}{x}$$

Step 3. Finally use the result above to find the value of $$\lim_{x\to 0} \left(\frac{\sin 4x}{x}\cdot-\cos(x)\right)$$

Can you take it from there?