Limit of e^x/x^2 as x approaches infinity using L'Hopital's Rule
Evaluate the following limit, which involves an indeterminate form.
Consider the function Evaluate
Hint
First check that direct substitution gives an indeterminate form of type . Since both numerator and denominator are differentiable and grow without bound, apply L'Hopital's Rule by differentiating numerator and denominator separately. You may need to apply the rule more than once — check the indeterminate form each time before doing so.
Step-by-step solution
As , both and , so the limit has the indeterminate form . This justifies applying L'Hopital's Rule: differentiate the numerator and denominator separately (not using the quotient rule) to get
The new limit is again of the form , so L'Hopital's Rule applies once more: differentiating top and bottom gives As , , so this limit is , meaning the original limit diverges to infinity.
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