{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-06-05T00:10:21.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2026-06-05T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":2510,"title":"Solving Quadratic Equations (Version 1)","description":"Quadratic equations have the form: ax^2 + bx + c = 0. Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2.  The quadratic formula can be used to find the roots:\r\n\r\n\u003c\u003chttps://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\u003e\u003e\r\n\r\nThe formula can be translated into the computation of two roots x1 and x2:\r\n\r\n  x1 = -b + ...\r\n  x2 = -b - ...\r\n\r\nComplete the function to solve the quadratic equation denoted by a, b, and c.  Assume the _discriminant_ --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real. ","description_html":"\u003cp\u003eQuadratic equations have the form: ax^2 + bx + c = 0. Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2.  The quadratic formula can be used to find the roots:\u003c/p\u003e\u003cimg src = \"https://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\"\u003e\u003cp\u003eThe formula can be translated into the computation of two roots x1 and x2:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003ex1 = -b + ...\r\nx2 = -b - ...\r\n\u003c/pre\u003e\u003cp\u003eComplete the function to solve the quadratic equation denoted by a, b, and c.  Assume the \u003ci\u003ediscriminant\u003c/i\u003e --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real.\u003c/p\u003e","function_template":"function [x1, x2] = SolveQuadraticEquation(a, b, c)\r\n  x1 = -b + ... ;\r\n  x2 = -b - ... ;\r\nend\r\n","test_suite":"%%\r\nqe_correct1_1 = -1;\r\nqe_correct1_2 = -2;\r\n[qe_result1_1, qe_result1_2] = SolveQuadraticEquation(1, 3, 2);\r\nassert( (abs(qe_result1_1 - qe_correct1_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_2) \u003c 0.0001) || ...\r\n        (abs(qe_result1_1 - qe_correct1_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_1) \u003c 0.0001) );\r\n%%\r\nqe_correct2_1 = 0.224745;\r\nqe_correct2_2 = -2.22474;\r\n[qe_result2_1, qe_result2_2] = SolveQuadraticEquation(2, 4, -1);\r\nassert( (abs(qe_result2_1 - qe_correct2_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_2) \u003c 0.0001) || ...\r\n        (abs(qe_result2_1 - qe_correct2_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_1) \u003c 0.0001) );\r\n%%\r\nqe_correct3_1 = -1;\r\nqe_correct3_2 = -1;\r\n[qe_result3_1, qe_result3_2] = SolveQuadraticEquation(2, 4, 2);\r\nassert( (abs(qe_result3_1 - qe_correct3_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_2) \u003c 0.0001) || ...\r\n        (abs(qe_result3_1 - qe_correct3_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_1) \u003c 0.0001) );\r\n","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":24594,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":506,"test_suite_updated_at":"2014-08-15T09:50:02.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2014-08-14T23:08:09.000Z","updated_at":"2026-04-27T20:54:12.000Z","published_at":"2014-08-15T09:50:02.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eQuadratic equations have the form: ax^2 + bx + c = 0. Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2. The quadratic formula can be used to find the roots:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:customXml w:element=\\\"image\\\"\u003e\u003cw:customXmlPr\u003e\u003cw:attr w:name=\\\"height\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"width\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"relationshipId\\\" w:val=\\\"rId1\\\"/\u003e\u003c/w:customXmlPr\u003e\u003c/w:customXml\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThe formula can be translated into the computation of two roots x1 and x2:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[x1 = -b + ...\\nx2 = -b - ...]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eComplete the function to solve the quadratic equation denoted by a, b, and c. Assume the\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003ediscriminant\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"},{\"partUri\":\"/media/image1.gif\",\"contentType\":\"image/gif\",\"content\":\"data:image/gif;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAMAAABEpIrGAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAC1QTFRFeHh4k5OT9vb2gYGBnJycwMDAt7e3ioqK0tLS7e3t29vb5OTkycnJ////b29vvCMpXwAAAKZJREFUeNq8k0sWwyAIAEXzh3D/41ZrahASklXZ6cxTEAz8EOGFsDvxTyECM0RHgJIwOEIt6VFYX19BAd0kKe8vTpn0vY9uheXoQjGYrICtf9mg3Qgo+kt12fE4sxQwaGFQXCdJmmshaV4EnKYxmgMO/pvJVJ92NrwNbSpnrJafUz1kYbRcjP121ii4EKDVIPnVx+n4hdBzKyhuBM21YLgSLOePAAMAW0UziCh1I3kAAAAASUVORK5CYII=\"}]}"},{"id":2529,"title":"Solving Quadratic Equations (Version 2)","description":"Before attempting this problem, solve version 1:  \u003chttps://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003e.\r\n\r\nIn this version, the discriminant can have any value.  Complete the function so if the discriminant is negative, the function returns values of NaN --- \"Not a Number\" --- for x1 and x2.  Otherwise, the function computes x1 and x2 as before using the formula\r\n\r\n\u003c\u003chttps://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\u003e\u003e\r\n","description_html":"\u003cp\u003eBefore attempting this problem, solve version 1:  \u003ca href = \"https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\"\u003ehttps://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003c/a\u003e.\u003c/p\u003e\u003cp\u003eIn this version, the discriminant can have any value.  Complete the function so if the discriminant is negative, the function returns values of NaN --- \"Not a Number\" --- for x1 and x2.  Otherwise, the function computes x1 and x2 as before using the formula\u003c/p\u003e\u003cimg src = \"https://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\"\u003e","function_template":"function [x1, x2] = SolveQuadraticEquation(a, b, c)\r\n\r\nend","test_suite":"%%\r\nqe_correct1_1 = -1;\r\nqe_correct1_2 = -2;\r\n[qe_result1_1, qe_result1_2] = SolveQuadraticEquation(1, 3, 2);\r\nassert( (abs(qe_result1_1 - qe_correct1_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_2) \u003c 0.0001) || ...\r\n        (abs(qe_result1_1 - qe_correct1_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_1) \u003c 0.0001) );\r\n%%\r\nqe_correct2_1 = 0.224745;\r\nqe_correct2_2 = -2.22474;\r\n[qe_result2_1, qe_result2_2] = SolveQuadraticEquation(2, 4, -1);\r\nassert( (abs(qe_result2_1 - qe_correct2_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_2) \u003c 0.0001) || ...\r\n        (abs(qe_result2_1 - qe_correct2_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_1) \u003c 0.0001) );\r\n%%\r\nqe_correct3_1 = -1;\r\nqe_correct3_2 = -1;\r\n[qe_result3_1, qe_result3_2] = SolveQuadraticEquation(2, 4, 2);\r\nassert( (abs(qe_result3_1 - qe_correct3_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_2) \u003c 0.0001) || ...\r\n        (abs(qe_result3_1 - qe_correct3_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_1) \u003c 0.0001) );\r\n%%\r\n[qe_result4_1, qe_result4_2] = SolveQuadraticEquation(4, 4, 4);\r\nassert( isnan(qe_result4_1) \u0026\u0026 isnan(qe_result4_2) );\r\n%%\r\n[qe_result5_1, qe_result5_2] = SolveQuadraticEquation(9.1, 12, 4.1);\r\nassert( isnan(qe_result5_1) \u0026\u0026 isnan(qe_result5_2) );\r\n","published":true,"deleted":false,"likes_count":0,"comments_count":1,"created_by":24594,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":90,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2014-08-25T23:26:04.000Z","updated_at":"2026-03-16T12:13:52.000Z","published_at":"2014-08-25T23:42:27.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eBefore attempting this problem, solve version 1: \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026lt;https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026gt;.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eIn this version, the discriminant can have any value. Complete the function so if the discriminant is negative, the function returns values of NaN --- \\\"Not a Number\\\" --- for x1 and x2. 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Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2.  The quadratic formula can be used to find the roots:\r\n\r\n\u003c\u003chttps://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\u003e\u003e\r\n\r\nThe formula can be translated into the computation of two roots x1 and x2:\r\n\r\n  x1 = -b + ...\r\n  x2 = -b - ...\r\n\r\nComplete the function to solve the quadratic equation denoted by a, b, and c.  Assume the _discriminant_ --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real. ","description_html":"\u003cp\u003eQuadratic equations have the form: ax^2 + bx + c = 0. Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2.  The quadratic formula can be used to find the roots:\u003c/p\u003e\u003cimg src = \"https://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\"\u003e\u003cp\u003eThe formula can be translated into the computation of two roots x1 and x2:\u003c/p\u003e\u003cpre class=\"language-matlab\"\u003ex1 = -b + ...\r\nx2 = -b - ...\r\n\u003c/pre\u003e\u003cp\u003eComplete the function to solve the quadratic equation denoted by a, b, and c.  Assume the \u003ci\u003ediscriminant\u003c/i\u003e --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real.\u003c/p\u003e","function_template":"function [x1, x2] = SolveQuadraticEquation(a, b, c)\r\n  x1 = -b + ... ;\r\n  x2 = -b - ... ;\r\nend\r\n","test_suite":"%%\r\nqe_correct1_1 = -1;\r\nqe_correct1_2 = -2;\r\n[qe_result1_1, qe_result1_2] = SolveQuadraticEquation(1, 3, 2);\r\nassert( (abs(qe_result1_1 - qe_correct1_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_2) \u003c 0.0001) || ...\r\n        (abs(qe_result1_1 - qe_correct1_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_1) \u003c 0.0001) );\r\n%%\r\nqe_correct2_1 = 0.224745;\r\nqe_correct2_2 = -2.22474;\r\n[qe_result2_1, qe_result2_2] = SolveQuadraticEquation(2, 4, -1);\r\nassert( (abs(qe_result2_1 - qe_correct2_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_2) \u003c 0.0001) || ...\r\n        (abs(qe_result2_1 - qe_correct2_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_1) \u003c 0.0001) );\r\n%%\r\nqe_correct3_1 = -1;\r\nqe_correct3_2 = -1;\r\n[qe_result3_1, qe_result3_2] = SolveQuadraticEquation(2, 4, 2);\r\nassert( (abs(qe_result3_1 - qe_correct3_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_2) \u003c 0.0001) || ...\r\n        (abs(qe_result3_1 - qe_correct3_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_1) \u003c 0.0001) );\r\n","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":24594,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":506,"test_suite_updated_at":"2014-08-15T09:50:02.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2014-08-14T23:08:09.000Z","updated_at":"2026-04-27T20:54:12.000Z","published_at":"2014-08-15T09:50:02.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eQuadratic equations have the form: ax^2 + bx + c = 0. Example: x^2 + 3x + 2 = 0, where a = 1, b = 3, and c = 2. The equation has 2 real solutions (roots): x = -1 and x = -2. The quadratic formula can be used to find the roots:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:customXml w:element=\\\"image\\\"\u003e\u003cw:customXmlPr\u003e\u003cw:attr w:name=\\\"height\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"width\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"relationshipId\\\" w:val=\\\"rId1\\\"/\u003e\u003c/w:customXmlPr\u003e\u003c/w:customXml\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThe formula can be translated into the computation of two roots x1 and x2:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[x1 = -b + ...\\nx2 = -b - ...]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eComplete the function to solve the quadratic equation denoted by a, b, and c. Assume the\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:rPr\u003e\u003cw:i/\u003e\u003c/w:rPr\u003e\u003cw:t\u003ediscriminant\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e --- b^2 - 4ac --- is not negative, ensuring that x1 and x2 are real.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"},{\"partUri\":\"/media/image1.gif\",\"contentType\":\"image/gif\",\"content\":\"data:image/gif;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAMAAABEpIrGAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAC1QTFRFeHh4k5OT9vb2gYGBnJycwMDAt7e3ioqK0tLS7e3t29vb5OTkycnJ////b29vvCMpXwAAAKZJREFUeNq8k0sWwyAIAEXzh3D/41ZrahASklXZ6cxTEAz8EOGFsDvxTyECM0RHgJIwOEIt6VFYX19BAd0kKe8vTpn0vY9uheXoQjGYrICtf9mg3Qgo+kt12fE4sxQwaGFQXCdJmmshaV4EnKYxmgMO/pvJVJ92NrwNbSpnrJafUz1kYbRcjP121ii4EKDVIPnVx+n4hdBzKyhuBM21YLgSLOePAAMAW0UziCh1I3kAAAAASUVORK5CYII=\"}]}"},{"id":2529,"title":"Solving Quadratic Equations (Version 2)","description":"Before attempting this problem, solve version 1:  \u003chttps://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003e.\r\n\r\nIn this version, the discriminant can have any value.  Complete the function so if the discriminant is negative, the function returns values of NaN --- \"Not a Number\" --- for x1 and x2.  Otherwise, the function computes x1 and x2 as before using the formula\r\n\r\n\u003c\u003chttps://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\u003e\u003e\r\n","description_html":"\u003cp\u003eBefore attempting this problem, solve version 1:  \u003ca href = \"https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\"\u003ehttps://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003c/a\u003e.\u003c/p\u003e\u003cp\u003eIn this version, the discriminant can have any value.  Complete the function so if the discriminant is negative, the function returns values of NaN --- \"Not a Number\" --- for x1 and x2.  Otherwise, the function computes x1 and x2 as before using the formula\u003c/p\u003e\u003cimg src = \"https://dl.dropboxusercontent.com/u/57773343/__IMAGES/QuadraticSolution1.gif\"\u003e","function_template":"function [x1, x2] = SolveQuadraticEquation(a, b, c)\r\n\r\nend","test_suite":"%%\r\nqe_correct1_1 = -1;\r\nqe_correct1_2 = -2;\r\n[qe_result1_1, qe_result1_2] = SolveQuadraticEquation(1, 3, 2);\r\nassert( (abs(qe_result1_1 - qe_correct1_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_2) \u003c 0.0001) || ...\r\n        (abs(qe_result1_1 - qe_correct1_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result1_2 - qe_correct1_1) \u003c 0.0001) );\r\n%%\r\nqe_correct2_1 = 0.224745;\r\nqe_correct2_2 = -2.22474;\r\n[qe_result2_1, qe_result2_2] = SolveQuadraticEquation(2, 4, -1);\r\nassert( (abs(qe_result2_1 - qe_correct2_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_2) \u003c 0.0001) || ...\r\n        (abs(qe_result2_1 - qe_correct2_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result2_2 - qe_correct2_1) \u003c 0.0001) );\r\n%%\r\nqe_correct3_1 = -1;\r\nqe_correct3_2 = -1;\r\n[qe_result3_1, qe_result3_2] = SolveQuadraticEquation(2, 4, 2);\r\nassert( (abs(qe_result3_1 - qe_correct3_1) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_2) \u003c 0.0001) || ...\r\n        (abs(qe_result3_1 - qe_correct3_2) \u003c 0.0001  \u0026\u0026 ...\r\n         abs(qe_result3_2 - qe_correct3_1) \u003c 0.0001) );\r\n%%\r\n[qe_result4_1, qe_result4_2] = SolveQuadraticEquation(4, 4, 4);\r\nassert( isnan(qe_result4_1) \u0026\u0026 isnan(qe_result4_2) );\r\n%%\r\n[qe_result5_1, qe_result5_2] = SolveQuadraticEquation(9.1, 12, 4.1);\r\nassert( isnan(qe_result5_1) \u0026\u0026 isnan(qe_result5_2) );\r\n","published":true,"deleted":false,"likes_count":0,"comments_count":1,"created_by":24594,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":90,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":1,"created_at":"2014-08-25T23:26:04.000Z","updated_at":"2026-03-16T12:13:52.000Z","published_at":"2014-08-25T23:42:27.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/image\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/media/image1.gif\"}],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eBefore attempting this problem, solve version 1: \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\\\"\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026lt;https://www.mathworks.com/matlabcentral/cody/problems/2510-solving-quadratic-equations-version-1\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e\u0026gt;.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eIn this version, the discriminant can have any value. Complete the function so if the discriminant is negative, the function returns values of NaN --- \\\"Not a Number\\\" --- for x1 and x2. Otherwise, the function computes x1 and x2 as before using the formula\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:customXml w:element=\\\"image\\\"\u003e\u003cw:customXmlPr\u003e\u003cw:attr w:name=\\\"height\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"width\\\" w:val=\\\"-1\\\"/\u003e\u003cw:attr w:name=\\\"relationshipId\\\" w:val=\\\"rId1\\\"/\u003e\u003c/w:customXmlPr\u003e\u003c/w:customXml\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"},{\"partUri\":\"/media/image1.gif\",\"contentType\":\"image/gif\",\"content\":\"data:image/gif;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAMAAABEpIrGAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAC1QTFRFeHh4k5OT9vb2gYGBnJycwMDAt7e3ioqK0tLS7e3t29vb5OTkycnJ////b29vvCMpXwAAAKZJREFUeNq8k0sWwyAIAEXzh3D/41ZrahASklXZ6cxTEAz8EOGFsDvxTyECM0RHgJIwOEIt6VFYX19BAd0kKe8vTpn0vY9uheXoQjGYrICtf9mg3Qgo+kt12fE4sxQwaGFQXCdJmmshaV4EnKYxmgMO/pvJVJ92NrwNbSpnrJafUz1kYbRcjP121ii4EKDVIPnVx+n4hdBzKyhuBM21YLgSLOePAAMAW0UziCh1I3kAAAAASUVORK5CYII=\"}]}"}],"errors":[],"facets":[[],[{"value":"easy","count":2,"selected":false}]],"term":"tag:\"quadraticequations\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}