// Numbas version: exam_results_page_options {"name": "Grainne's copy of Amit's copy of Arithmetics of complex numbers II", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variables": {"e6": {"description": "", "definition": "s5*random(3..9)", "name": "e6", "group": "Ungrouped variables", "templateType": "anything"}, "z3": {"description": "", "definition": "s6*random(1..9)+e6*i", "name": "z3", "group": "Ungrouped variables", "templateType": "anything"}, "f6": {"description": "", "definition": "s6*random(1..9)", "name": "f6", "group": "Ungrouped variables", "templateType": "anything"}, "a": {"description": "", "definition": "s1*random(1..9)+s2*random(1..9)*i", "name": "a", "group": "Ungrouped variables", "templateType": "anything"}, "a3": {"description": "", "definition": "s1*random(1..9)", "name": "a3", "group": "Ungrouped variables", "templateType": "anything"}, "s4": {"description": "", "definition": "random(1,-1)", "name": "s4", "group": "Ungrouped variables", "templateType": "anything"}, "c3": {"description": "", "definition": "s3*random(1..9)", "name": "c3", "group": "Ungrouped variables", "templateType": "anything"}, "z2": {"description": "", "definition": "s2*random(1..9)+d6*i", "name": "z2", "group": "Ungrouped variables", "templateType": "anything"}, "s5": {"description": "", "definition": "random(1,-1)", "name": "s5", "group": "Ungrouped variables", "templateType": "anything"}, "d3": {"description": "", "definition": "s4*random(1..9)", "name": "d3", "group": "Ungrouped variables", "templateType": "anything"}, "s6": {"description": "", "definition": "random(1,-1)", "name": "s6", "group": "Ungrouped variables", "templateType": "anything"}, "s3": {"description": "", "definition": "random(1,-1)", "name": "s3", "group": "Ungrouped variables", "templateType": "anything"}, "d6": {"description": "", "definition": "s4*random(1..9)", "name": "d6", "group": "Ungrouped variables", "templateType": "anything"}, "z4": {"description": "", "definition": "s6*s2*random(1..9)+s3*s5*random(1..9)*i", "name": "z4", "group": "Ungrouped variables", "templateType": "anything"}, "s2": {"description": "", "definition": "random(1,-1)", "name": "s2", "group": "Ungrouped variables", "templateType": "anything"}, "s1": {"description": "", "definition": "random(1,-1)", "name": "s1", "group": "Ungrouped variables", "templateType": "anything"}, "b3": {"description": "", "definition": "s2*random(1..9)", "name": "b3", "group": "Ungrouped variables", "templateType": "anything"}, "z1": {"description": "", "definition": "s3*random(1..9)+f6*i", "name": "z1", "group": "Ungrouped variables", "templateType": "anything"}}, "functions": {}, "name": "Grainne's copy of Amit's copy of Arithmetics of complex numbers II", "variablesTest": {"maxRuns": 100, "condition": ""}, "type": "question", "variable_groups": [], "preamble": {"js": "", "css": ""}, "ungrouped_variables": ["a", "f6", "s3", "s2", "s1", "d3", "s6", "s5", "s4", "c3", "a3", "b3", "d6", "e6", "z4", "z1", "z2", "z3"], "showQuestionGroupNames": false, "rulesets": {"std": ["all", "!collectNumbers", "fractionNumbers", "!noLeadingMinus"]}, "metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "

Multiplication and addition of complex numbers. Four parts.

", "notes": "

15/07/2015:

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Added tags.

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4/7/2012

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Added tags

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Same problem in Complex Numbers_2. Question a - sometimes the complex number is generated as a/(b+i*c) but sometimes the complex number is displayed as a decimal, i.e. 0.0975609756+0.1219512195i if this happens then the question is invalid. This is an issue on github.

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16/07/2012:

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Issue above resolved. Also forbid decimals and brackets. Questions cannot now be answered by simply repeating the expression.

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Added formal cba name mas104220122013CBA1_3 as a tag

"}, "tags": ["addition of complex numbers", "algebra of complex numbers", "checked2015", "complex numbers", "mas1602", "MAS1602", "multiplication of complex numbers"], "advice": "

a)

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The solution is given by:

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$\\simplify[std]{{e6*i}}(\\simplify[std]{{a}})=\\simplify[std]{{a*e6*i}}$

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b)

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$\\simplify[std]{{a}*{z4}={a*z4}}$

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c)
\\[ \\begin{eqnarray*} \\simplify[std,!otherNumbers]{{a}*({a3} + {b3} * i + {c3} * i ^ 2 + {d3} * i ^ 3)}&=&\\simplify[std]{{a}*{a3 + b3 * i + c3 * i ^ 2 + d3 * i ^ 3}}\\\\ &=&\\simplify[std]{{a*(a3 + b3 * i + c3 * i ^ 2 + d3 * i ^ 3)}} \\end{eqnarray*} \\]
d)

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This can be calculated by using the formula twice, firstly to multiply out the first two sets of parentheses, 

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and then to multiply the result of that calculation by the third set of parentheses.

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So we obtain:
\\[ \\begin{eqnarray*} (\\var{a})(\\var{z1})(\\var{z3})&=&((\\var{a})(\\var{z1}))(\\var{z3})\\\\ &=&(\\var{a*(z1)})(\\var{z3})\\\\ &=&\\var{a*(z1)*(z3)} \\end{eqnarray*} \\]

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Input all numbers as fractions or integers. Also do not include brackets in your answers.

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$\\var{e6*i}(\\simplify[std]{{a}})\\;=\\;$[[0]].

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Input all numbers as fractions or integers. Also do not include brackets in your answers.

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$(\\simplify[std]{{a}})(\\simplify[std]{{z4}})\\;=\\;$[[0]].

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Input all numbers as fractions or integers. Also do not include brackets in your answers.

", "showStrings": false}, "vsetrange": [0, 1], "checkvariablenames": false, "variableReplacements": [], "showpreview": true, "answer": "{(a3 + b3 * i + c3 * i ^ 2 + d3 * i ^ 3)*a}", "vsetrangepoints": 5, "checkingaccuracy": 0.001}], "prompt": "

$\\simplify[std,!otherNumbers]{{a}*({a3} + {b3} * i + {c3} * i ^ 2 + {d3} * i ^ 3)}\\;=\\;$[[0]].

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Input all numbers as fractions or integers. Also do not include brackets in your answers.

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$(\\simplify[std]{{a}})(\\simplify[std]{ {z1}})(\\simplify[std]{ {z3}})\\;=\\;$[[0]].

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Find the following complex numbers in the form $a+bi\\;$ where $a$ and $b$ are real.

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Input all numbers as fractions or integers. Also do not include brackets in your answers.

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