Indefinite Integrals
Definition (Indefinite Integrals) A function
is called an antiderivative of a given function
on an interval
if
for all
in
Theorem (Indefinite Integrals) If
is an antiderivative of the continuous function
then any other antiderivative,
of
must have the form
where
is some constant.
The notation
where
is an arbitrary constant means that
is an antiderivative of
It is called the indefinite integral of
and satisfies the condition that
for all
in the domain of
It is important to remember that
represents a family of functions.
Example (Indefinite Integrals) Find the family of antiderivatives of the function
and write an equation using the indefinite integral notation.
Solution. If
then
and so an antiderivative of sine is
By the Antiderivative Theorem, the most general antiderivative is
Therefore,
where
is an arbitrary constant.
Proposition (Indefinite Integrals) Let
and
be differentiable functions of
such that
Then
where
is an antiderivative of
This process is called integration by substitution.
Example (Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_38.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_38.gif)
Solution. Let
then
and by substitution, we have,
![indefinite integrals _gr_41.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_41.gif)
![indefinite integrals _gr_42.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_42.gif)
![indefinite integrals _gr_43.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_43.gif)
![indefinite integrals _gr_44.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_44.gif)
![indefinite integrals _gr_45.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_45.gif)
where
is an arbitrary constant. Alternatively, we use
and then
and,
![indefinite integrals _gr_49.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_49.gif)
![indefinite integrals _gr_50.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_50.gif)
![indefinite integrals _gr_51.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_51.gif)
![indefinite integrals _gr_52.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_52.gif)
Example (Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_54.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_54.gif)
Solution. Let
and then
and so
![indefinite integrals _gr_57.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_57.gif)
![indefinite integrals _gr_58.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_58.gif)
![indefinite integrals _gr_59.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_59.gif)
![indefinite integrals _gr_60.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_60.gif)
![indefinite integrals _gr_61.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_61.gif)
where
is an arbitrary constant.
Example(Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_64.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_64.gif)
Solution. Let
then
and then
![indefinite integrals _gr_67.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_67.gif)
![indefinite integrals _gr_68.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_68.gif)
![indefinite integrals _gr_69.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_69.gif)
![indefinite integrals _gr_70.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_70.gif)
![indefinite integrals _gr_71.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_71.gif)
where
is an arbitrary constant.
Example (Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_74.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_74.gif)
Solution. Let
then
and
![indefinite integrals _gr_77.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_77.gif)
![indefinite integrals _gr_78.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_78.gif)
![indefinite integrals _gr_79.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_79.gif)
![indefinite integrals _gr_80.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_80.gif)
![indefinite integrals _gr_81.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_81.gif)
![indefinite integrals _gr_82.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_82.gif)
where
is an arbitrary constant.
Example (Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_85.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_85.gif)
Solution. Let
then
and
![indefinite integrals _gr_88.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_88.gif)
![indefinite integrals _gr_89.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_89.gif)
![indefinite integrals _gr_90.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_90.gif)
![indefinite integrals _gr_91.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_91.gif)
where
is an arbitrary constant.
Example (Indefinite Integrals) Use integration by substitution to evaluate
![indefinite integrals _gr_94.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_94.gif)
Solution. Let
then
and
![indefinite integrals _gr_97.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_97.gif)
![indefinite integrals _gr_98.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_98.gif)
![indefinite integrals _gr_99.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_99.gif)
![indefinite integrals _gr_100.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_100.gif)
![indefinite integrals _gr_101.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_101.gif)
where
is an arbitrary constant. Alternatively, let
then
and
![indefinite integrals _gr_105.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_105.gif)
![indefinite integrals _gr_106.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_106.gif)
![indefinite integrals _gr_107.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_107.gif)
![indefinite integrals _gr_108.gif]](pages/indefinite-integrals/Images/indefinite-integrals_gr_108.gif)
Cite this as: Indefinite Integrals Published by Library of Math -- Online math organized by subject into topics.
Written by Smith, David A.
http://www.libraryofmath.com/indefinite-integrals.html
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