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Section 2.1 L’Hopital’s Rule

Subsection 2.1.1 L’Hopital’s Rule Summary

  1. Determine if the limit is an indeterminate form, and if so, then what form it is.
  2. If it’s \(\frac{0}{0}\) or \(\frac{\infty}{\infty}\text{,}\) then apply L’Hopital’s rule directly.
  3. If it’s \(0 \cdot \infty\) (or \(\infty \cdot 0\)), flip one of the terms to convert it to \(\frac{0}{0}\) or \(\frac{\infty}{\infty}\) (whichever is more convenient).
  4. If it’s \(\infty - \infty\text{,}\) then write it as one fraction first, and then continue.
  5. If it’s an indeterminate form with an exponent, like \(1^{\infty}\text{,}\) \(0^0\text{,}\) or \(\infty^0\text{,}\) then first use logarithms.
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