How to differentiate $ exp left{ int^t_sf(u)du right} $ w.r.t. $t$?












1












$begingroup$


I have looked and looked in my calculus books but couldn't find the answer to a problem I am facing of of the following form:



$$g(t) = exp left{ int^t_sf(u)du right} \
frac{partial g(t)}{partial t} = ? $$



How do I differentiate $g(t)$ w.r.t $t$?



$s$ is fixed.










share|cite|improve this question











$endgroup$

















    1












    $begingroup$


    I have looked and looked in my calculus books but couldn't find the answer to a problem I am facing of of the following form:



    $$g(t) = exp left{ int^t_sf(u)du right} \
    frac{partial g(t)}{partial t} = ? $$



    How do I differentiate $g(t)$ w.r.t $t$?



    $s$ is fixed.










    share|cite|improve this question











    $endgroup$















      1












      1








      1





      $begingroup$


      I have looked and looked in my calculus books but couldn't find the answer to a problem I am facing of of the following form:



      $$g(t) = exp left{ int^t_sf(u)du right} \
      frac{partial g(t)}{partial t} = ? $$



      How do I differentiate $g(t)$ w.r.t $t$?



      $s$ is fixed.










      share|cite|improve this question











      $endgroup$




      I have looked and looked in my calculus books but couldn't find the answer to a problem I am facing of of the following form:



      $$g(t) = exp left{ int^t_sf(u)du right} \
      frac{partial g(t)}{partial t} = ? $$



      How do I differentiate $g(t)$ w.r.t $t$?



      $s$ is fixed.







      calculus integration derivatives






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Jan 14 at 10:43









      BowPark

      560720




      560720










      asked Jan 13 at 21:15









      econmajorreconmajorr

      104




      104






















          3 Answers
          3






          active

          oldest

          votes


















          1












          $begingroup$

          It is a composite of the function $h(t):= exp(t)$ and $k(t):= int_s^t f(u) , mathrm{d} u$. By the chain rule we have $g'(t) = k'(t) h'(k(t))$. On the other hand, the fundamental theorem of calculus says that $k'(t) = f(t)$. Both together imply that
          $$g'(t) = k'(t) h'(k(t)) = f(t) exp(k(t)) = f(t) g(t).$$
          Note that this argument also proves that $g$ is differentiable. This steps are valid provided that $f$ is contiuous.






          share|cite|improve this answer











          $endgroup$





















            1












            $begingroup$

            Chain rule; we know how to differentiate $exp$ and we know how to differentiate $int_s^t f(u),du$ (the Fundamental Theorem), so we just combine those with the chain rule..






            share|cite|improve this answer









            $endgroup$





















              0












              $begingroup$

              We have $$frac{partial g(t)}{partial t}{=expleft{ int^t_sf(u)du right}cdot {partial int^t_sf(u)duover partial t}\=g(t)cdot Big(f(t)-f(s)Big)}$$can't proceed any further.






              share|cite|improve this answer









              $endgroup$













                Your Answer





                StackExchange.ifUsing("editor", function () {
                return StackExchange.using("mathjaxEditing", function () {
                StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
                StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
                });
                });
                }, "mathjax-editing");

                StackExchange.ready(function() {
                var channelOptions = {
                tags: "".split(" "),
                id: "69"
                };
                initTagRenderer("".split(" "), "".split(" "), channelOptions);

                StackExchange.using("externalEditor", function() {
                // Have to fire editor after snippets, if snippets enabled
                if (StackExchange.settings.snippets.snippetsEnabled) {
                StackExchange.using("snippets", function() {
                createEditor();
                });
                }
                else {
                createEditor();
                }
                });

                function createEditor() {
                StackExchange.prepareEditor({
                heartbeatType: 'answer',
                autoActivateHeartbeat: false,
                convertImagesToLinks: true,
                noModals: true,
                showLowRepImageUploadWarning: true,
                reputationToPostImages: 10,
                bindNavPrevention: true,
                postfix: "",
                imageUploader: {
                brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
                contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
                allowUrls: true
                },
                noCode: true, onDemand: true,
                discardSelector: ".discard-answer"
                ,immediatelyShowMarkdownHelp:true
                });


                }
                });














                draft saved

                draft discarded


















                StackExchange.ready(
                function () {
                StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3072534%2fhow-to-differentiate-exp-left-intt-sfudu-right-w-r-t-t%23new-answer', 'question_page');
                }
                );

                Post as a guest















                Required, but never shown

























                3 Answers
                3






                active

                oldest

                votes








                3 Answers
                3






                active

                oldest

                votes









                active

                oldest

                votes






                active

                oldest

                votes









                1












                $begingroup$

                It is a composite of the function $h(t):= exp(t)$ and $k(t):= int_s^t f(u) , mathrm{d} u$. By the chain rule we have $g'(t) = k'(t) h'(k(t))$. On the other hand, the fundamental theorem of calculus says that $k'(t) = f(t)$. Both together imply that
                $$g'(t) = k'(t) h'(k(t)) = f(t) exp(k(t)) = f(t) g(t).$$
                Note that this argument also proves that $g$ is differentiable. This steps are valid provided that $f$ is contiuous.






                share|cite|improve this answer











                $endgroup$


















                  1












                  $begingroup$

                  It is a composite of the function $h(t):= exp(t)$ and $k(t):= int_s^t f(u) , mathrm{d} u$. By the chain rule we have $g'(t) = k'(t) h'(k(t))$. On the other hand, the fundamental theorem of calculus says that $k'(t) = f(t)$. Both together imply that
                  $$g'(t) = k'(t) h'(k(t)) = f(t) exp(k(t)) = f(t) g(t).$$
                  Note that this argument also proves that $g$ is differentiable. This steps are valid provided that $f$ is contiuous.






                  share|cite|improve this answer











                  $endgroup$
















                    1












                    1








                    1





                    $begingroup$

                    It is a composite of the function $h(t):= exp(t)$ and $k(t):= int_s^t f(u) , mathrm{d} u$. By the chain rule we have $g'(t) = k'(t) h'(k(t))$. On the other hand, the fundamental theorem of calculus says that $k'(t) = f(t)$. Both together imply that
                    $$g'(t) = k'(t) h'(k(t)) = f(t) exp(k(t)) = f(t) g(t).$$
                    Note that this argument also proves that $g$ is differentiable. This steps are valid provided that $f$ is contiuous.






                    share|cite|improve this answer











                    $endgroup$



                    It is a composite of the function $h(t):= exp(t)$ and $k(t):= int_s^t f(u) , mathrm{d} u$. By the chain rule we have $g'(t) = k'(t) h'(k(t))$. On the other hand, the fundamental theorem of calculus says that $k'(t) = f(t)$. Both together imply that
                    $$g'(t) = k'(t) h'(k(t)) = f(t) exp(k(t)) = f(t) g(t).$$
                    Note that this argument also proves that $g$ is differentiable. This steps are valid provided that $f$ is contiuous.







                    share|cite|improve this answer














                    share|cite|improve this answer



                    share|cite|improve this answer








                    edited Jan 14 at 10:10

























                    answered Jan 13 at 21:19









                    p4schp4sch

                    5,450318




                    5,450318























                        1












                        $begingroup$

                        Chain rule; we know how to differentiate $exp$ and we know how to differentiate $int_s^t f(u),du$ (the Fundamental Theorem), so we just combine those with the chain rule..






                        share|cite|improve this answer









                        $endgroup$


















                          1












                          $begingroup$

                          Chain rule; we know how to differentiate $exp$ and we know how to differentiate $int_s^t f(u),du$ (the Fundamental Theorem), so we just combine those with the chain rule..






                          share|cite|improve this answer









                          $endgroup$
















                            1












                            1








                            1





                            $begingroup$

                            Chain rule; we know how to differentiate $exp$ and we know how to differentiate $int_s^t f(u),du$ (the Fundamental Theorem), so we just combine those with the chain rule..






                            share|cite|improve this answer









                            $endgroup$



                            Chain rule; we know how to differentiate $exp$ and we know how to differentiate $int_s^t f(u),du$ (the Fundamental Theorem), so we just combine those with the chain rule..







                            share|cite|improve this answer












                            share|cite|improve this answer



                            share|cite|improve this answer










                            answered Jan 13 at 21:19









                            jmerryjmerry

                            15.3k1632




                            15.3k1632























                                0












                                $begingroup$

                                We have $$frac{partial g(t)}{partial t}{=expleft{ int^t_sf(u)du right}cdot {partial int^t_sf(u)duover partial t}\=g(t)cdot Big(f(t)-f(s)Big)}$$can't proceed any further.






                                share|cite|improve this answer









                                $endgroup$


















                                  0












                                  $begingroup$

                                  We have $$frac{partial g(t)}{partial t}{=expleft{ int^t_sf(u)du right}cdot {partial int^t_sf(u)duover partial t}\=g(t)cdot Big(f(t)-f(s)Big)}$$can't proceed any further.






                                  share|cite|improve this answer









                                  $endgroup$
















                                    0












                                    0








                                    0





                                    $begingroup$

                                    We have $$frac{partial g(t)}{partial t}{=expleft{ int^t_sf(u)du right}cdot {partial int^t_sf(u)duover partial t}\=g(t)cdot Big(f(t)-f(s)Big)}$$can't proceed any further.






                                    share|cite|improve this answer









                                    $endgroup$



                                    We have $$frac{partial g(t)}{partial t}{=expleft{ int^t_sf(u)du right}cdot {partial int^t_sf(u)duover partial t}\=g(t)cdot Big(f(t)-f(s)Big)}$$can't proceed any further.







                                    share|cite|improve this answer












                                    share|cite|improve this answer



                                    share|cite|improve this answer










                                    answered Jan 13 at 22:47









                                    Mostafa AyazMostafa Ayaz

                                    17k31039




                                    17k31039






























                                        draft saved

                                        draft discarded




















































                                        Thanks for contributing an answer to Mathematics Stack Exchange!


                                        • Please be sure to answer the question. Provide details and share your research!

                                        But avoid



                                        • Asking for help, clarification, or responding to other answers.

                                        • Making statements based on opinion; back them up with references or personal experience.


                                        Use MathJax to format equations. MathJax reference.


                                        To learn more, see our tips on writing great answers.




                                        draft saved


                                        draft discarded














                                        StackExchange.ready(
                                        function () {
                                        StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3072534%2fhow-to-differentiate-exp-left-intt-sfudu-right-w-r-t-t%23new-answer', 'question_page');
                                        }
                                        );

                                        Post as a guest















                                        Required, but never shown





















































                                        Required, but never shown














                                        Required, but never shown












                                        Required, but never shown







                                        Required, but never shown

































                                        Required, but never shown














                                        Required, but never shown












                                        Required, but never shown







                                        Required, but never shown







                                        Popular posts from this blog

                                        Human spaceflight

                                        Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

                                        張江高科駅