L'Hospital's Rule may be applied more than once when evaluating

MATHEMATICS · Single correct · CBSE · Mathematics · Integrals · Integrals

Problem

L'Hospital's Rule may be applied more than once when evaluating lim⁡x→af(x)g(x)\displaystyle\lim_{x\to a}\frac{f(x)}{g(x)}. After differentiating once, which condition must still hold at x=ax=a to justify taking derivatives a second time? (a) Both f′′f'' and g′′g'' exist and are continuous at x=ax=a (b) The quotient f′(x)g′(x)\dfrac{f'(x)}{g'(x)} is again an indeterminate form 00\tfrac{0}{0} or ∞∞\tfrac{\infty}{\infty} (c) lim⁡x→af′(x)=0\displaystyle\lim_{x\to a}f'(x)=0 and lim⁡x→ag′(x)=0\displaystyle\lim_{x\to a}g'(x)=0 (d) g′(x)≠0  for all x near ag'(x)\neq0\,\text{ for all }x\text{ near }a but lim⁡x→af′(x)=0\displaystyle\lim_{x\to a}f'(x)=0

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