Imaginary Roots of quadratics and Graph

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
2
down vote

favorite












I have this equation: $x^2-4x+5 = 0$ . Its roots are imaginary $2 pm i$ and I read in Algebra book/resource somewhere that to graph a quadratic equation with imaginary/complex roots, you need a complex-plane. But I can graph this (it is a parabola) with real numbers without any need for complex plane. What gap is there in my knowledge of algebra ?



enter image description here







share|cite|improve this question
























    up vote
    2
    down vote

    favorite












    I have this equation: $x^2-4x+5 = 0$ . Its roots are imaginary $2 pm i$ and I read in Algebra book/resource somewhere that to graph a quadratic equation with imaginary/complex roots, you need a complex-plane. But I can graph this (it is a parabola) with real numbers without any need for complex plane. What gap is there in my knowledge of algebra ?



    enter image description here







    share|cite|improve this question






















      up vote
      2
      down vote

      favorite









      up vote
      2
      down vote

      favorite











      I have this equation: $x^2-4x+5 = 0$ . Its roots are imaginary $2 pm i$ and I read in Algebra book/resource somewhere that to graph a quadratic equation with imaginary/complex roots, you need a complex-plane. But I can graph this (it is a parabola) with real numbers without any need for complex plane. What gap is there in my knowledge of algebra ?



      enter image description here







      share|cite|improve this question












      I have this equation: $x^2-4x+5 = 0$ . Its roots are imaginary $2 pm i$ and I read in Algebra book/resource somewhere that to graph a quadratic equation with imaginary/complex roots, you need a complex-plane. But I can graph this (it is a parabola) with real numbers without any need for complex plane. What gap is there in my knowledge of algebra ?



      enter image description here









      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Aug 9 at 16:37









      Arnuld

      4511




      4511




















          1 Answer
          1






          active

          oldest

          votes

















          up vote
          2
          down vote



          accepted










          There is no need of the complex plane to graph a quadratic function. But you need it in order to see the roots of your specific quadric.






          share|cite|improve this answer




















            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',
            convertImagesToLinks: true,
            noModals: false,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            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%2f2877420%2fimaginary-roots-of-quadratics-and-graph%23new-answer', 'question_page');

            );

            Post as a guest






























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes








            up vote
            2
            down vote



            accepted










            There is no need of the complex plane to graph a quadratic function. But you need it in order to see the roots of your specific quadric.






            share|cite|improve this answer
























              up vote
              2
              down vote



              accepted










              There is no need of the complex plane to graph a quadratic function. But you need it in order to see the roots of your specific quadric.






              share|cite|improve this answer






















                up vote
                2
                down vote



                accepted







                up vote
                2
                down vote



                accepted






                There is no need of the complex plane to graph a quadratic function. But you need it in order to see the roots of your specific quadric.






                share|cite|improve this answer












                There is no need of the complex plane to graph a quadratic function. But you need it in order to see the roots of your specific quadric.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Aug 9 at 16:41









                José Carlos Santos

                115k1699177




                115k1699177






















                     

                    draft saved


                    draft discarded


























                     


                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function ()
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2877420%2fimaginary-roots-of-quadratics-and-graph%23new-answer', 'question_page');

                    );

                    Post as a guest













































































                    這個網誌中的熱門文章

                    How to combine Bézier curves to a surface?

                    Carbon dioxide

                    Why am i infinitely getting the same tweet with the Twitter Search API?