Are these expressions not equal? Mathematica output is ambiguousChecking if two trigonometric expressions are equalHow to group the powers of one variable?How do I simplify an embedded sub-expression without affecting other sub-expressions?Why are some equal expressions more equal than others?How can I get Mathematica to simplify my expression?Equality of Reciprocal with Negative ExponentMake Mathematica not simplify an expressionWSTP simplifying expression from CHow do I handle complicated algebraic manipulations?Smart way of simplifying an expression with square roots?

How to implement a feedback to keep the DC gain at zero for this conceptual passive filter?

Count the occurrence of each unique word in the file

What does "Scientists rise up against statistical significance" mean? (Comment in Nature)

How do you respond to a colleague from another team when they're wrongly expecting that you'll help them?

Are paving bricks differently sized for sand bedding vs mortar bedding?

Not using 's' for he/she/it

What should you do when eye contact makes your subordinate uncomfortable?

How to explain what's wrong with this application of the chain rule?

How can "mimic phobia" be cured or prevented?

Lowest total scrabble score

Can I sign legal documents with a smiley face?

What is Cash Advance APR?

Is it safe to use olive oil to clean the ear wax?

copy and scale one figure (wheel)

The screen of my macbook suddenly broken down how can I do to recover

Strong empirical falsification of quantum mechanics based on vacuum energy density

"Spoil" vs "Ruin"

What should you do if you miss a job interview (deliberately)?

Terse Method to Swap Lowest for Highest?

Is there a name for this algorithm to calculate the concentration of a mixture of two solutions containing the same solute?

lightning-datatable row number error

Fear of getting stuck on one programming language / technology that is not used in my country

Is it better practice to read straight from sheet music rather than memorize it?

Which one is correct as adjective “protruding” or “protruded”?



Are these expressions not equal? Mathematica output is ambiguous


Checking if two trigonometric expressions are equalHow to group the powers of one variable?How do I simplify an embedded sub-expression without affecting other sub-expressions?Why are some equal expressions more equal than others?How can I get Mathematica to simplify my expression?Equality of Reciprocal with Negative ExponentMake Mathematica not simplify an expressionWSTP simplifying expression from CHow do I handle complicated algebraic manipulations?Smart way of simplifying an expression with square roots?













5












$begingroup$


The following plot indicates that the first expression equals the second. But how can I use Mathematica to show that is true:



Plot[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), P, 0, 1]


An attempt to simplify indicates the expressions are not equal:



FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])]


That gives the following answer:



(Log[-1 + 1/P] + Log[-(P/(-1 + P))])/Log[10]


enter image description here










share|improve this question









$endgroup$







  • 3




    $begingroup$
    Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
    $endgroup$
    – Sjoerd Smit
    yesterday







  • 1




    $begingroup$
    In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
    $endgroup$
    – Henrik Schumacher
    yesterday






  • 1




    $begingroup$
    Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
    $endgroup$
    – J. M. is slightly pensive
    yesterday















5












$begingroup$


The following plot indicates that the first expression equals the second. But how can I use Mathematica to show that is true:



Plot[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), P, 0, 1]


An attempt to simplify indicates the expressions are not equal:



FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])]


That gives the following answer:



(Log[-1 + 1/P] + Log[-(P/(-1 + P))])/Log[10]


enter image description here










share|improve this question









$endgroup$







  • 3




    $begingroup$
    Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
    $endgroup$
    – Sjoerd Smit
    yesterday







  • 1




    $begingroup$
    In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
    $endgroup$
    – Henrik Schumacher
    yesterday






  • 1




    $begingroup$
    Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
    $endgroup$
    – J. M. is slightly pensive
    yesterday













5












5








5





$begingroup$


The following plot indicates that the first expression equals the second. But how can I use Mathematica to show that is true:



Plot[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), P, 0, 1]


An attempt to simplify indicates the expressions are not equal:



FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])]


That gives the following answer:



(Log[-1 + 1/P] + Log[-(P/(-1 + P))])/Log[10]


enter image description here










share|improve this question









$endgroup$




The following plot indicates that the first expression equals the second. But how can I use Mathematica to show that is true:



Plot[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), P, 0, 1]


An attempt to simplify indicates the expressions are not equal:



FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])]


That gives the following answer:



(Log[-1 + 1/P] + Log[-(P/(-1 + P))])/Log[10]


enter image description here







plotting simplifying-expressions






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked yesterday









user120911user120911

73628




73628







  • 3




    $begingroup$
    Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
    $endgroup$
    – Sjoerd Smit
    yesterday







  • 1




    $begingroup$
    In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
    $endgroup$
    – Henrik Schumacher
    yesterday






  • 1




    $begingroup$
    Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
    $endgroup$
    – J. M. is slightly pensive
    yesterday












  • 3




    $begingroup$
    Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
    $endgroup$
    – Sjoerd Smit
    yesterday







  • 1




    $begingroup$
    In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
    $endgroup$
    – Henrik Schumacher
    yesterday






  • 1




    $begingroup$
    Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
    $endgroup$
    – J. M. is slightly pensive
    yesterday







3




3




$begingroup$
Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
$endgroup$
– Sjoerd Smit
yesterday





$begingroup$
Add the option Assumptions -> 0 < P < 1 to FullSimplify and it will tell you they are the same on that domain. Without assumptions, Mathematica will try to solve the equation for every possible complex value of P and the two equations are not generally equal due to branch cuts.
$endgroup$
– Sjoerd Smit
yesterday





1




1




$begingroup$
In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
$endgroup$
– Henrik Schumacher
yesterday




$begingroup$
In addition to what Sjoerd said: Evaluating FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/ Log[10]), P > 1] reveals that the expressions are not equal for arbitrary real P. So Mathematica would have lied if she had simplified FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10])] to 0.
$endgroup$
– Henrik Schumacher
yesterday




1




1




$begingroup$
Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
$endgroup$
– J. M. is slightly pensive
yesterday




$begingroup$
Always remember: Mathematica always assumes variables are complex-valued unless told otherwise. You did not tell FullSimplify[] what you know about P, so of course you get a general result.
$endgroup$
– J. M. is slightly pensive
yesterday










1 Answer
1






active

oldest

votes


















11












$begingroup$

You can ask Mathematica when this expression is zero, assuming we work on the reals:



Reduce[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]) == 0, P, Reals]
(* 0 < P < 1 *)


FullSimplify will confirm that result.



FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), 0 < P < 1]
(* 0 *)





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
    );



    );













    draft saved

    draft discarded


















    StackExchange.ready(
    function ()
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f193756%2fare-these-expressions-not-equal-mathematica-output-is-ambiguous%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









    11












    $begingroup$

    You can ask Mathematica when this expression is zero, assuming we work on the reals:



    Reduce[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]) == 0, P, Reals]
    (* 0 < P < 1 *)


    FullSimplify will confirm that result.



    FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), 0 < P < 1]
    (* 0 *)





    share|improve this answer









    $endgroup$

















      11












      $begingroup$

      You can ask Mathematica when this expression is zero, assuming we work on the reals:



      Reduce[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]) == 0, P, Reals]
      (* 0 < P < 1 *)


      FullSimplify will confirm that result.



      FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), 0 < P < 1]
      (* 0 *)





      share|improve this answer









      $endgroup$















        11












        11








        11





        $begingroup$

        You can ask Mathematica when this expression is zero, assuming we work on the reals:



        Reduce[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]) == 0, P, Reals]
        (* 0 < P < 1 *)


        FullSimplify will confirm that result.



        FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), 0 < P < 1]
        (* 0 *)





        share|improve this answer









        $endgroup$



        You can ask Mathematica when this expression is zero, assuming we work on the reals:



        Reduce[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]) == 0, P, Reals]
        (* 0 < P < 1 *)


        FullSimplify will confirm that result.



        FullSimplify[(-(Log[(1 - P)/P]/Log[10])) - (Log[-(P/(-1 + P))]/Log[10]), 0 < P < 1]
        (* 0 *)






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered yesterday









        SzabolcsSzabolcs

        162k14444942




        162k14444942



























            draft saved

            draft discarded
















































            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%2f193756%2fare-these-expressions-not-equal-mathematica-output-is-ambiguous%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

            Sum ergo cogito? 1 nng

            419 nièngy_Soadمي 19bal1.5o_g

            Queiggey Chernihivv 9NnOo i Zw X QqKk LpB