// Numbas version: finer_feedback_settings {"name": "General solution to 2nd order PDE: student can pick names of the arbitrary functions.", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "General solution to 2nd order PDE: student can pick names of the arbitrary functions.", "tags": [], "metadata": {"description": "

The student has to write the general solution of a 2nd order PDE. They can choose the names of their arbitrary functions of $x$ and $y$.

\n

The marking algorithm finds the names of the functions of $x$ and $y$ in the student's answer, and replaces them with $\\sin(x)$ and $\\cos(y)$ (these could be changed) so that the expression can be evaluated.

", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "

\\[ u_{xy} = \\simplify{{a}x + {b}y} \\]

", "advice": "

For arbitrary functions $F$ and $G$, the general solution is:

\n

\\[ u(x,y) = \\simplify{ {a}*x^2y/2 + {b}x*y^2/2 + F(x) + G(x) \\]

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Write the general solution $u(x,y)$.

", "answer": "{a}*x^2y/2 + {b}*x*y^2/2 + F(x)+G(y)", "showPreview": true, "checkingType": "absdiff", "checkingAccuracy": 0.001, "failureRate": 1, "vsetRangePoints": 5, "vsetRange": [0, 1], "checkVariableNames": false, "singleLetterVariables": true, "allowUnknownFunctions": true, "implicitFunctionComposition": false, "caseSensitive": false, "valuegenerators": [{"name": "f", "value": ""}, {"name": "g", "value": ""}, {"name": "x", "value": ""}, {"name": "y", "value": ""}]}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}, {"name": "Shweta Sharma", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/21418/"}], "resources": []}]}], "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}, {"name": "Shweta Sharma", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/21418/"}]}