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

Wanted: 5.25 floppy to usb adapter

Where is this triangular-shaped space station from?

How do we edit a novel that's written by several people?

Why do neural networks need so many training examples to perform?

Why is commutativity optional in multiplication for rings?

What is the wife of a henpecked husband called?

Is the theory of the category of topological spaces computable?

How to avoid being sexist when trying to employ someone to function in a very sexist environment?

Meth dealer reference in Family Guy

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

Can a hotel cancel a confirmed reservation?

What can I substitute for soda pop in a sweet pork recipe?

Find the number of ways to express 1050 as sum of consecutive integers

Can a person refuse a presidential pardon?

Am I a Rude Number?

How do Japanese speakers determine the implied topic when none has been mentioned?

Yeshiva University RIETS Semicha Yorei and Yadin

Can I retract my name from an already published manuscript?

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

Walking in a rotating spacecraft and Newton's 3rd Law of Motion

4 Spheres all touching each other??

If all harmonics are generated by plucking, how does a guitar string produce a pure frequency sound?

Inventor that creates machine that grabs man from future

Is Draco canonically good-looking?



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

            Why do type traits not work with types in namespace scope?What are POD types in C++?Why can templates only be...

            Will tsunami waves travel forever if there was no land?Why do tsunami waves begin with the water flowing away...

            Simple Scan not detecting my scanner (Brother DCP-7055W)Brother MFC-L2700DW printer can print, can't...