- #1

navneet9431

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<Moderator's note: Moved from a technical forum and thus no template.>

$$\lim_{x \to 0} \cos(\pi/2\cos(x))/x^2$$

I tried to evaluate the limit this way,

$$\lim_{x \to 0} \cos(\pi/2\cdot1)/x^2$$ since $$\cos0=1$$

$$\lim_{x \to 0} \cos(\pi/2\cdot1)/x^2=\lim_{x \to 0} 0/x^2$$

Now apply L'Hospital's Rule twice,

$$\lim_{x \to 0} 0/2(x)=\lim_{x \to 0} 0/2=0$$

So,this way the answer is zero.

Can you please explain where am I doing wrong?

I will be thankful for help!

$$\lim_{x \to 0} \cos(\pi/2\cos(x))/x^2$$

I tried to evaluate the limit this way,

$$\lim_{x \to 0} \cos(\pi/2\cdot1)/x^2$$ since $$\cos0=1$$

$$\lim_{x \to 0} \cos(\pi/2\cdot1)/x^2=\lim_{x \to 0} 0/x^2$$

Now apply L'Hospital's Rule twice,

$$\lim_{x \to 0} 0/2(x)=\lim_{x \to 0} 0/2=0$$

So,this way the answer is zero.

Can you please explain where am I doing wrong?

I will be thankful for help!

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