Finding an integral using a table?Integral of $cosleft(frac1xright), dx$How to solve this indefinite integral...

What is better: yes / no radio, or simple checkbox?

Dilemma of explaining to interviewer that he is the reason for declining second interview

What to do when being responsible for data protection in your lab, yet advice is ignored?

If a druid in Wild Shape swallows a creature whole, then turns back to her normal form, what happens?

What is the purpose of easy combat scenarios that don't need resource expenditure?

Which aircraft had such a luxurious-looking navigator's station?

What's a good word to describe a public place that looks like it wouldn't be rough?

Why zero tolerance on nudity in space?

Criticizing long fiction. How is it different from short?

Metadata API deployments are failing in Spring '19

LTSpice: When running a linear AC simulation, how to view the voltage ratio between two voltages?

Why is working on the same position for more than 15 years not a red flag?

Word to be used for "standing with your toes pointing out"

How to push a box with physics engine by another object?

How to approximate rolls for potions of healing using only d6's?

Incompressible fluid definition

Is the theory of the category of topological spaces computable?

How to add multiple differently colored borders around a node?

Why do members of Congress in committee hearings ask witnesses the same question multiple times?

Meaning of すきっとした

Finding an integral using a table?

Do commercial flights continue with an engine out?

Why is c4 a better move in this position?

Why is my solution for the partial pressures of two different gases incorrect?



Finding an integral using a table?


Integral of $cosleft(frac1xright), dx$How to solve this indefinite integral using integral substitution?Two solutions for the same integral question, which approach is correct/better to solve?Solving integral without simplifying equationFinding the integral of $x^2sqrt[3]{1-x}$How to find the value of this indefinite integral?Finding double integral of this region using polar coordinates?Solving Integral with Symbolic Computation (Sympy), Division and Tricky LimitsProving Table of Integral Integral (Trigonometric Substitution)Using a table of integrals for solving these integrals













2












$begingroup$


Am I correct for pattern matching this integral?



I have



$$int frac{sqrt{9x^2+4}}{x^2}dx$$



Does this pattern match with:



$$int frac{sqrt{a^2 + x^2}}{x^2}dx = -frac{a^2 + x^2}{x} + ln(x + sqrt{a^2 + x^2}) + c$$



If I factor out the 9, I get



$$= 3 int frac{sqrt{x^2 + frac{4}{9}}}{x^2}$$
with $a = frac{2}{3}$



I get:
$$3 left( - frac{sqrt{frac{4}{9}+x^2}}{x} + lnleft(x+sqrt{frac{4}{9}+x^2}right) +cright)$$



Is this the right track?



Wolfram winds up with a different answer though:



enter image description here










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
    $endgroup$
    – Minus One-Twelfth
    3 hours ago










  • $begingroup$
    Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
    $endgroup$
    – xbh
    3 hours ago






  • 1




    $begingroup$
    One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
    $endgroup$
    – David K
    1 hour ago
















2












$begingroup$


Am I correct for pattern matching this integral?



I have



$$int frac{sqrt{9x^2+4}}{x^2}dx$$



Does this pattern match with:



$$int frac{sqrt{a^2 + x^2}}{x^2}dx = -frac{a^2 + x^2}{x} + ln(x + sqrt{a^2 + x^2}) + c$$



If I factor out the 9, I get



$$= 3 int frac{sqrt{x^2 + frac{4}{9}}}{x^2}$$
with $a = frac{2}{3}$



I get:
$$3 left( - frac{sqrt{frac{4}{9}+x^2}}{x} + lnleft(x+sqrt{frac{4}{9}+x^2}right) +cright)$$



Is this the right track?



Wolfram winds up with a different answer though:



enter image description here










share|cite|improve this question











$endgroup$








  • 1




    $begingroup$
    Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
    $endgroup$
    – Minus One-Twelfth
    3 hours ago










  • $begingroup$
    Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
    $endgroup$
    – xbh
    3 hours ago






  • 1




    $begingroup$
    One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
    $endgroup$
    – David K
    1 hour ago














2












2








2


2



$begingroup$


Am I correct for pattern matching this integral?



I have



$$int frac{sqrt{9x^2+4}}{x^2}dx$$



Does this pattern match with:



$$int frac{sqrt{a^2 + x^2}}{x^2}dx = -frac{a^2 + x^2}{x} + ln(x + sqrt{a^2 + x^2}) + c$$



If I factor out the 9, I get



$$= 3 int frac{sqrt{x^2 + frac{4}{9}}}{x^2}$$
with $a = frac{2}{3}$



I get:
$$3 left( - frac{sqrt{frac{4}{9}+x^2}}{x} + lnleft(x+sqrt{frac{4}{9}+x^2}right) +cright)$$



Is this the right track?



Wolfram winds up with a different answer though:



enter image description here










share|cite|improve this question











$endgroup$




Am I correct for pattern matching this integral?



I have



$$int frac{sqrt{9x^2+4}}{x^2}dx$$



Does this pattern match with:



$$int frac{sqrt{a^2 + x^2}}{x^2}dx = -frac{a^2 + x^2}{x} + ln(x + sqrt{a^2 + x^2}) + c$$



If I factor out the 9, I get



$$= 3 int frac{sqrt{x^2 + frac{4}{9}}}{x^2}$$
with $a = frac{2}{3}$



I get:
$$3 left( - frac{sqrt{frac{4}{9}+x^2}}{x} + lnleft(x+sqrt{frac{4}{9}+x^2}right) +cright)$$



Is this the right track?



Wolfram winds up with a different answer though:



enter image description here







integration






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited 1 hour ago









clathratus

4,745337




4,745337










asked 3 hours ago









Jwan622Jwan622

2,20611632




2,20611632








  • 1




    $begingroup$
    Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
    $endgroup$
    – Minus One-Twelfth
    3 hours ago










  • $begingroup$
    Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
    $endgroup$
    – xbh
    3 hours ago






  • 1




    $begingroup$
    One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
    $endgroup$
    – David K
    1 hour ago














  • 1




    $begingroup$
    Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
    $endgroup$
    – Minus One-Twelfth
    3 hours ago










  • $begingroup$
    Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
    $endgroup$
    – xbh
    3 hours ago






  • 1




    $begingroup$
    One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
    $endgroup$
    – David K
    1 hour ago








1




1




$begingroup$
Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
$endgroup$
– Minus One-Twelfth
3 hours ago




$begingroup$
Have you tried manipulating your answer to look like Wolfram's? Also, note that it's fine if your answer differs from Wolfram's by a constant.
$endgroup$
– Minus One-Twelfth
3 hours ago












$begingroup$
Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
$endgroup$
– xbh
3 hours ago




$begingroup$
Actually they are the same, because the answer given by WA is simply yours plus one constant $3 log (3/2)$.
$endgroup$
– xbh
3 hours ago




1




1




$begingroup$
One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
$endgroup$
– David K
1 hour ago




$begingroup$
One quick way to check the result is to put your formula into Wolfram Alpha (without the constant, which in this case is just adding $3c$ to the result) and subtract the formula Wolfram Alpha gave (again omitting the constant). If the result is a flat constant function then your integral is correct.
$endgroup$
– David K
1 hour ago










1 Answer
1






active

oldest

votes


















4












$begingroup$

You are indeed correct. Note that in an indefinite integral, perfectly valid answers can be separated by (any) constant.



The first term in Wolfram's answer can be rewritten:



$3ln{(frac32(x+sqrt{frac49 + x^2}))} = 3ln{(x+sqrt{frac49 + x^2})} + 3lnfrac 32$



and the second term can be rearranged to be identical to your other term.



So your answers are separated by a constant. That's fine. You're right.






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%2f3134306%2ffinding-an-integral-using-a-table%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    4












    $begingroup$

    You are indeed correct. Note that in an indefinite integral, perfectly valid answers can be separated by (any) constant.



    The first term in Wolfram's answer can be rewritten:



    $3ln{(frac32(x+sqrt{frac49 + x^2}))} = 3ln{(x+sqrt{frac49 + x^2})} + 3lnfrac 32$



    and the second term can be rearranged to be identical to your other term.



    So your answers are separated by a constant. That's fine. You're right.






    share|cite|improve this answer









    $endgroup$


















      4












      $begingroup$

      You are indeed correct. Note that in an indefinite integral, perfectly valid answers can be separated by (any) constant.



      The first term in Wolfram's answer can be rewritten:



      $3ln{(frac32(x+sqrt{frac49 + x^2}))} = 3ln{(x+sqrt{frac49 + x^2})} + 3lnfrac 32$



      and the second term can be rearranged to be identical to your other term.



      So your answers are separated by a constant. That's fine. You're right.






      share|cite|improve this answer









      $endgroup$
















        4












        4








        4





        $begingroup$

        You are indeed correct. Note that in an indefinite integral, perfectly valid answers can be separated by (any) constant.



        The first term in Wolfram's answer can be rewritten:



        $3ln{(frac32(x+sqrt{frac49 + x^2}))} = 3ln{(x+sqrt{frac49 + x^2})} + 3lnfrac 32$



        and the second term can be rearranged to be identical to your other term.



        So your answers are separated by a constant. That's fine. You're right.






        share|cite|improve this answer









        $endgroup$



        You are indeed correct. Note that in an indefinite integral, perfectly valid answers can be separated by (any) constant.



        The first term in Wolfram's answer can be rewritten:



        $3ln{(frac32(x+sqrt{frac49 + x^2}))} = 3ln{(x+sqrt{frac49 + x^2})} + 3lnfrac 32$



        and the second term can be rearranged to be identical to your other term.



        So your answers are separated by a constant. That's fine. You're right.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered 3 hours ago









        DeepakDeepak

        17.3k11537




        17.3k11537






























            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%2f3134306%2ffinding-an-integral-using-a-table%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

            Щит и меч (фильм) Содержание Названия серий | Сюжет |...

            Венесуэла на летних Олимпийских играх 2000 Содержание Состав...

            Meter-Bus Содержание Параметры шины | Стандартизация |...