All AP Calculus BC Resources
Example Questions
Example Question #22 : L'hospital's Rule
Find the limit if it exists
Hint: Use L'Hospital's rule
Directly evaluating for yields the indeterminate form
we are able to apply L'Hospital's rule which states that if the limit is in indeterminate form when evaluated, then
As such the limit in the problem becomes
Evaluating for yields
As such
and thus
Example Question #482 : Ap Calculus Bc
Evaluate using L'hopital's rule.
This important limit from elementary limit theory is usually proven using trigonometric arguments, but it can be shown using L'hopital's rule too.
Example Question #483 : Ap Calculus Bc
Evaluate the limit:
The limit does not exist
When evaluating the limit using normal methods, we find that the indeterminate form results. When this occurs, we must use L'Hopital's Rule, which states that for .
Taking the derivative of the top and bottom functions and evaluating the limit, we get
The derivatives were found using the following rules:
, ,
Example Question #213 : Derivatives
Evaluate the limit:
The limit does not exist
When evaluating the limit using normal methods, we find that we get the indeterminate form . When this occurs, we must use L'Hopital's Rule to evaluate the limit. The rule states that for the limits for which the indeterminate forms result,
Taking the derivatives for our limit, we get
The derivatives were found using the following rules:
,
Example Question #482 : Ap Calculus Bc
Evaluate the limit:
The limit does not exist
When evaluating the limit using normal methods (substitution), we get the indeterminate form . When this (or ) occurs, we must use L'Hopital's Rule to evaluate the limit. The rule states that when an indeterminate form results from the limit,
Taking the derivatives in our limit, we get
The derivatives were found using the following rules:
, , ,
Example Question #481 : Ap Calculus Bc
Evaluate the limit
.
Admittedly a more computationally intensive problem, we begin by trying to plug in into the limit directly, but we get the indeterminate form .
We then apply L'Hôpital's rule and try again:
.
However, plugging in still yields the indeterminate form , so we are forced to apply L'Hôpital's rule a second time:
.
This time, plugging in does not produce an indeterminate form, so we may evaluate the limit by setting as follows:
.
Example Question #22 : Euler's Method And L'hopital's Rule
Evaluate the limit
.
Simply plugging in into the expression yields the indeterminate form of , so we must resort to using L'Hôpital's rule. We take the derivative of the numerator and denominator, and then look at the limit again.
This time, when we plug in , we do not get an indeterminate form, so we can evaluate the limit by setting :
.