Use definition as a derivative (as a limit) problem

Thread starter CrossFit415
Start date Oct 25, 2011
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Definition Derivative Limit

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The discussion revolves around evaluating the limit of the expression (2cosθ - 1) / (3θ - π) as θ approaches π/3, which results in an indeterminate form of 0/0. Participants question whether to apply L'Hôpital's rule by differentiating the numerator and denominator, specifically considering the derivative of cosθ as -sinθ. There is confusion about how this limit relates to the definition of the derivative. Clarification is sought on the exact formulation of the problem to better understand its context. The conversation highlights the challenges in applying limit concepts in calculus.

Oct 25, 2011

CrossFit415

Limit → pi/3 \frac{2cosθ-1}{3θ-pi}

I plugged in pi/3 and I got 0/0. I'm not sure that's right way.

Would I need to change the derivative of cosθ to -sinθ? Or just plug pi/3 ?

Last edited: Oct 25, 2011

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Oct 25, 2011

vela

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Could you state the problem exactly as it's given? I'm not seeing how this is related to the definition of the derivative.

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