Finding the area between two curves with Integrate The 2019 Stack Overflow Developer Survey...

How to notate time signature switching consistently every measure

Falsification in Math vs Science

How can I add encounters in the Lost Mine of Phandelver campaign without giving PCs too much XP?

Is there a way to generate a uniformly distributed point on a sphere from a fixed amount of random real numbers?

"as much details as you can remember"

Why isn't the circumferential light around the M87 black hole's event horizon symmetric?

How do I free up internal storage if I don't have any apps downloaded?

Can withdrawing asylum be illegal?

Can I have a signal generator on while it's not connected?

Straighten subgroup lattice

Getting crown tickets for Statue of Liberty

What could be the right powersource for 15 seconds lifespan disposable giant chainsaw?

Is it a good practice to use a static variable in a Test Class and use that in the actual class instead of Test.isRunningTest()?

Likelihood that a superbug or lethal virus could come from a landfill

Can a flute soloist sit?

Will it cause any balance problems to have PCs level up and gain the benefits of a long rest mid-fight?

Is Cinnamon a desktop environment or a window manager? (Or both?)

Correct punctuation for showing a character's confusion

Is bread bad for ducks?

Can there be female White Walkers?

Why was M87 targeted for the Event Horizon Telescope instead of Sagittarius A*?

What is the meaning of Triage in Cybersec world?

How do you keep chess fun when your opponent constantly beats you?

What is the most efficient way to store a numeric range?



Finding the area between two curves with Integrate



The 2019 Stack Overflow Developer Survey Results Are InHow to evaluate this indefinite integral $csc(4x)sin(x)$Finding the centroid of the area between two curvesRevolving the area between two functions about an axisArea enclosed by two functionsComputing the area between two curvesIntegrate to calculate enclosed areaInteresting discrepencies between integrate functionsFinding the volume enclosed by two surfaces of revolutionFinding an area enclosed by 4 curvesApproximate the relationship between 6 nonlinear functions involving elliptic integrals












2












$begingroup$


I'm trying to solve and approximate the area between the two graphs. Right now, my functions are stored as



f[x_] := 3 Sin[x]
g[x_] := x - 1


and then I tried to integrate by evaluating



Integrate[Abs[f[x] - g[x]], x]


Instead of getting an answer, I just get the exact same thing I inputted



Integrate[Abs[f[x] - g[x]], x]


How do I fix this?










share|improve this question









New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$












  • $begingroup$
    You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
    $endgroup$
    – Michael E2
    1 hour ago
















2












$begingroup$


I'm trying to solve and approximate the area between the two graphs. Right now, my functions are stored as



f[x_] := 3 Sin[x]
g[x_] := x - 1


and then I tried to integrate by evaluating



Integrate[Abs[f[x] - g[x]], x]


Instead of getting an answer, I just get the exact same thing I inputted



Integrate[Abs[f[x] - g[x]], x]


How do I fix this?










share|improve this question









New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$












  • $begingroup$
    You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
    $endgroup$
    – Michael E2
    1 hour ago














2












2








2





$begingroup$


I'm trying to solve and approximate the area between the two graphs. Right now, my functions are stored as



f[x_] := 3 Sin[x]
g[x_] := x - 1


and then I tried to integrate by evaluating



Integrate[Abs[f[x] - g[x]], x]


Instead of getting an answer, I just get the exact same thing I inputted



Integrate[Abs[f[x] - g[x]], x]


How do I fix this?










share|improve this question









New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$




I'm trying to solve and approximate the area between the two graphs. Right now, my functions are stored as



f[x_] := 3 Sin[x]
g[x_] := x - 1


and then I tried to integrate by evaluating



Integrate[Abs[f[x] - g[x]], x]


Instead of getting an answer, I just get the exact same thing I inputted



Integrate[Abs[f[x] - g[x]], x]


How do I fix this?







calculus-and-analysis






share|improve this question









New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|improve this question









New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|improve this question




share|improve this question








edited 44 mins ago









m_goldberg

88.6k873200




88.6k873200






New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked 1 hour ago









RyanRyan

111




111




New contributor




Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






Ryan is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • $begingroup$
    You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
    $endgroup$
    – Michael E2
    1 hour ago


















  • $begingroup$
    You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
    $endgroup$
    – Michael E2
    1 hour ago
















$begingroup$
You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
$endgroup$
– Michael E2
1 hour ago




$begingroup$
You can format inline code and code blocks by selecting the code and clicking the {} button above the edit window. The edit window help button ? is useful for learning how to format your questions and answers. You may also find this meta Q&A helpful
$endgroup$
– Michael E2
1 hour ago










3 Answers
3






active

oldest

votes


















2












$begingroup$

Use Assumptions:



Integrate[Abs[f[x] - g[x]], x, Assumptions -> x [Element] Reals]


Mathematica graphics



Or try RealAbs instead of Abs:



Integrate[RealAbs[f[x] - g[x]], x]


Mathematica graphics



(They are equivalent antiderivatives.)



To get the area between the graphs, you need also to solve for the points of intersection.



area = Integrate[
Abs[f[x] - g[x]], {x, Sequence @@ MinMax[x /. Solve[f[x] == g[x], x, Reals]]}]


Mathematica graphics



The area is approximately:



N[area]
(* 5.57475 *)





share|improve this answer











$endgroup$













  • $begingroup$
    RealAbs is awesome to know about! :O
    $endgroup$
    – Kagaratsch
    58 mins ago



















1












$begingroup$

You need to add assumptions, like this



 Integrate[Abs[f[x] - g[x]], x, Assumptions :> Element[x, Reals]]


Mathematica graphics






share|improve this answer









$endgroup$





















    0












    $begingroup$

    Assuming your functions



    f[x_] := 3 Sin[x] 
    g[x_] := x - 1


    are real valued, you can use square root of square to parametrize the absolute value. This then gives:



    Integrate[Sqrt[(f[x] - g[x])^2], x]



    (((-2 + x) x + 6 Cos[x]) Sqrt[(-1 + x - 3 Sin[x])^2])/(2 (-1 + x -
    3 Sin[x]))







    share|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: "387"
      };
      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: false,
      noModals: true,
      showLowRepImageUploadWarning: true,
      reputationToPostImages: null,
      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
      },
      onDemand: true,
      discardSelector: ".discard-answer"
      ,immediatelyShowMarkdownHelp:true
      });


      }
      });






      Ryan is a new contributor. Be nice, and check out our Code of Conduct.










      draft saved

      draft discarded


















      StackExchange.ready(
      function () {
      StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f195049%2ffinding-the-area-between-two-curves-with-integrate%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









      2












      $begingroup$

      Use Assumptions:



      Integrate[Abs[f[x] - g[x]], x, Assumptions -> x [Element] Reals]


      Mathematica graphics



      Or try RealAbs instead of Abs:



      Integrate[RealAbs[f[x] - g[x]], x]


      Mathematica graphics



      (They are equivalent antiderivatives.)



      To get the area between the graphs, you need also to solve for the points of intersection.



      area = Integrate[
      Abs[f[x] - g[x]], {x, Sequence @@ MinMax[x /. Solve[f[x] == g[x], x, Reals]]}]


      Mathematica graphics



      The area is approximately:



      N[area]
      (* 5.57475 *)





      share|improve this answer











      $endgroup$













      • $begingroup$
        RealAbs is awesome to know about! :O
        $endgroup$
        – Kagaratsch
        58 mins ago
















      2












      $begingroup$

      Use Assumptions:



      Integrate[Abs[f[x] - g[x]], x, Assumptions -> x [Element] Reals]


      Mathematica graphics



      Or try RealAbs instead of Abs:



      Integrate[RealAbs[f[x] - g[x]], x]


      Mathematica graphics



      (They are equivalent antiderivatives.)



      To get the area between the graphs, you need also to solve for the points of intersection.



      area = Integrate[
      Abs[f[x] - g[x]], {x, Sequence @@ MinMax[x /. Solve[f[x] == g[x], x, Reals]]}]


      Mathematica graphics



      The area is approximately:



      N[area]
      (* 5.57475 *)





      share|improve this answer











      $endgroup$













      • $begingroup$
        RealAbs is awesome to know about! :O
        $endgroup$
        – Kagaratsch
        58 mins ago














      2












      2








      2





      $begingroup$

      Use Assumptions:



      Integrate[Abs[f[x] - g[x]], x, Assumptions -> x [Element] Reals]


      Mathematica graphics



      Or try RealAbs instead of Abs:



      Integrate[RealAbs[f[x] - g[x]], x]


      Mathematica graphics



      (They are equivalent antiderivatives.)



      To get the area between the graphs, you need also to solve for the points of intersection.



      area = Integrate[
      Abs[f[x] - g[x]], {x, Sequence @@ MinMax[x /. Solve[f[x] == g[x], x, Reals]]}]


      Mathematica graphics



      The area is approximately:



      N[area]
      (* 5.57475 *)





      share|improve this answer











      $endgroup$



      Use Assumptions:



      Integrate[Abs[f[x] - g[x]], x, Assumptions -> x [Element] Reals]


      Mathematica graphics



      Or try RealAbs instead of Abs:



      Integrate[RealAbs[f[x] - g[x]], x]


      Mathematica graphics



      (They are equivalent antiderivatives.)



      To get the area between the graphs, you need also to solve for the points of intersection.



      area = Integrate[
      Abs[f[x] - g[x]], {x, Sequence @@ MinMax[x /. Solve[f[x] == g[x], x, Reals]]}]


      Mathematica graphics



      The area is approximately:



      N[area]
      (* 5.57475 *)






      share|improve this answer














      share|improve this answer



      share|improve this answer








      edited 55 mins ago

























      answered 59 mins ago









      Michael E2Michael E2

      150k12203482




      150k12203482












      • $begingroup$
        RealAbs is awesome to know about! :O
        $endgroup$
        – Kagaratsch
        58 mins ago


















      • $begingroup$
        RealAbs is awesome to know about! :O
        $endgroup$
        – Kagaratsch
        58 mins ago
















      $begingroup$
      RealAbs is awesome to know about! :O
      $endgroup$
      – Kagaratsch
      58 mins ago




      $begingroup$
      RealAbs is awesome to know about! :O
      $endgroup$
      – Kagaratsch
      58 mins ago











      1












      $begingroup$

      You need to add assumptions, like this



       Integrate[Abs[f[x] - g[x]], x, Assumptions :> Element[x, Reals]]


      Mathematica graphics






      share|improve this answer









      $endgroup$


















        1












        $begingroup$

        You need to add assumptions, like this



         Integrate[Abs[f[x] - g[x]], x, Assumptions :> Element[x, Reals]]


        Mathematica graphics






        share|improve this answer









        $endgroup$
















          1












          1








          1





          $begingroup$

          You need to add assumptions, like this



           Integrate[Abs[f[x] - g[x]], x, Assumptions :> Element[x, Reals]]


          Mathematica graphics






          share|improve this answer









          $endgroup$



          You need to add assumptions, like this



           Integrate[Abs[f[x] - g[x]], x, Assumptions :> Element[x, Reals]]


          Mathematica graphics







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 59 mins ago









          NasserNasser

          58.7k490206




          58.7k490206























              0












              $begingroup$

              Assuming your functions



              f[x_] := 3 Sin[x] 
              g[x_] := x - 1


              are real valued, you can use square root of square to parametrize the absolute value. This then gives:



              Integrate[Sqrt[(f[x] - g[x])^2], x]



              (((-2 + x) x + 6 Cos[x]) Sqrt[(-1 + x - 3 Sin[x])^2])/(2 (-1 + x -
              3 Sin[x]))







              share|improve this answer









              $endgroup$


















                0












                $begingroup$

                Assuming your functions



                f[x_] := 3 Sin[x] 
                g[x_] := x - 1


                are real valued, you can use square root of square to parametrize the absolute value. This then gives:



                Integrate[Sqrt[(f[x] - g[x])^2], x]



                (((-2 + x) x + 6 Cos[x]) Sqrt[(-1 + x - 3 Sin[x])^2])/(2 (-1 + x -
                3 Sin[x]))







                share|improve this answer









                $endgroup$
















                  0












                  0








                  0





                  $begingroup$

                  Assuming your functions



                  f[x_] := 3 Sin[x] 
                  g[x_] := x - 1


                  are real valued, you can use square root of square to parametrize the absolute value. This then gives:



                  Integrate[Sqrt[(f[x] - g[x])^2], x]



                  (((-2 + x) x + 6 Cos[x]) Sqrt[(-1 + x - 3 Sin[x])^2])/(2 (-1 + x -
                  3 Sin[x]))







                  share|improve this answer









                  $endgroup$



                  Assuming your functions



                  f[x_] := 3 Sin[x] 
                  g[x_] := x - 1


                  are real valued, you can use square root of square to parametrize the absolute value. This then gives:



                  Integrate[Sqrt[(f[x] - g[x])^2], x]



                  (((-2 + x) x + 6 Cos[x]) Sqrt[(-1 + x - 3 Sin[x])^2])/(2 (-1 + x -
                  3 Sin[x]))








                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered 1 hour ago









                  KagaratschKagaratsch

                  4,83831348




                  4,83831348






















                      Ryan is a new contributor. Be nice, and check out our Code of Conduct.










                      draft saved

                      draft discarded


















                      Ryan is a new contributor. Be nice, and check out our Code of Conduct.













                      Ryan is a new contributor. Be nice, and check out our Code of Conduct.












                      Ryan is a new contributor. Be nice, and check out our Code of Conduct.
















                      Thanks for contributing an answer to Mathematica 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%2fmathematica.stackexchange.com%2fquestions%2f195049%2ffinding-the-area-between-two-curves-with-integrate%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

                      Can't compile dgruyter and caption packagesLaTeX templates/packages for writing a patent specificationLatex...

                      Schneeberg (Smreczany) Bibliografia | Menu...

                      Hans Bellmer Spis treści Życiorys | Upamiętnienie | Przypisy | Bibliografia | Linki zewnętrzne |...