// Numbas version: exam_results_page_options {"name": "David's copy of Logs: subtraction to division inside", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"metadata": {"notes": "", "description": "", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "type": "question", "preamble": {"css": "", "js": ""}, "advice": "", "rulesets": {}, "question_groups": [{"pickingStrategy": "all-ordered", "name": "", "pickQuestions": 0, "questions": []}], "name": "David's copy of Logs: subtraction to division inside", "ungrouped_variables": ["num1", "num2", "ans1", "n1", "n2", "m1", "m2", "m3", "arg", "list", "b1", "b2"], "showQuestionGroupNames": false, "functions": {}, "tags": ["laws", "log laws", "logarithms", "logs", "rules"], "variablesTest": {"condition": "", "maxRuns": 100}, "variable_groups": [], "variables": {"arg": {"name": "arg", "group": "Ungrouped variables", "definition": "random(2..20)", "description": "", "templateType": "anything"}, "n2": {"name": "n2", "group": "Ungrouped variables", "definition": "random([2,3,5,7,11,13,17,19,23] except n1)", "description": "", "templateType": "anything"}, "m2": {"name": "m2", "group": "Ungrouped variables", "definition": "random(2..12 except m1)", "description": "", "templateType": "anything"}, "num2": {"name": "num2", "group": "Ungrouped variables", "definition": "random(-12..12 except [-1,0,1,num1])", "description": "", "templateType": "anything"}, "m1": {"name": "m1", "group": "Ungrouped variables", "definition": "random(2..12)", "description": "", "templateType": "anything"}, "n1": {"name": "n1", "group": "Ungrouped variables", "definition": "random([2,3,5,7,11,13,17,19,23])", "description": "", "templateType": "anything"}, "list": {"name": "list", "group": "Ungrouped variables", "definition": "reverse(sort(shuffle([2,3,4,5,10])[0..2]))", "description": "", "templateType": "anything"}, "ans1": {"name": "ans1", "group": "Ungrouped variables", "definition": "num1-num2", "description": "", "templateType": "anything"}, "b1": {"name": "b1", "group": "Ungrouped variables", "definition": "list[0]", "description": "", "templateType": "anything"}, "m3": {"name": "m3", "group": "Ungrouped variables", "definition": "random(2..12 except [m1,m2])", "description": "", "templateType": "anything"}, "num1": {"name": "num1", "group": "Ungrouped variables", "definition": "random(-12..12 except [-1,0,1])", "description": "", "templateType": "anything"}, "b2": {"name": "b2", "group": "Ungrouped variables", "definition": "list[1]", "description": "", "templateType": "anything"}}, "statement": "

Based on the definition of logarithms, determine the following:

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Suppose $\\log_b\\left(a\\right)=\\var{num1}$ and $\\log_b\\left(c\\right)=\\var{num2}$. Evaluate $\\log_b\\left(\\frac{a}{c}\\right)$ = [[0]].

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Here we are using the following log law

\n

\\[\\log_b(a)-\\log_b(c)=\\log_b\\left(\\frac{a}{c}\\right).\\]

\n

Notice, all the bases are the same. Also, notice how division inside the log becomes subtraction outside the log. 

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$\\log_b(\\var{n1})-\\log_b(\\var{n2})$ is equivalent to $\\log_b\\large($[[0]]$\\large)$.

", "showCorrectAnswer": true, "gaps": [{"maxValue": "{n1}/{n2}", "showPrecisionHint": false, "scripts": {}, "allowFractions": true, "type": "numberentry", "variableReplacementStrategy": "originalfirst", "marks": 1, "minValue": "{n1}/{n2}", "showCorrectAnswer": true, "variableReplacements": [], "correctAnswerFraction": true}], "variableReplacements": [], "steps": [{"type": "information", "scripts": {}, "variableReplacementStrategy": "originalfirst", "marks": 0, "prompt": "

Here we are using the following log law

\n

\\[\\log_b(a)-\\log_b(c)=\\log_b\\left(\\frac{a}{c}\\right).\\]

\n

Notice, all the bases are the same. Also, notice how division inside the log becomes subtraction outside the log. 

", "showCorrectAnswer": true, "variableReplacements": []}]}, {"type": "gapfill", "scripts": {}, "stepsPenalty": "1", "variableReplacementStrategy": "originalfirst", "marks": 0, "prompt": "

$\\log_b(\\var{m1})-\\log_b(\\var{m2})+\\log_b(\\var{m3})$ is equivalent to $\\log_b\\large($[[0]]$\\large)$.

", "showCorrectAnswer": true, "gaps": [{"maxValue": "{m1*m3}/{m2}", "showPrecisionHint": false, "scripts": {}, "allowFractions": true, "type": "numberentry", "variableReplacementStrategy": "originalfirst", "marks": 1, "minValue": "{m1*m3}/{m2}", "showCorrectAnswer": true, "variableReplacements": [], "correctAnswerFraction": true}], "variableReplacements": [], "steps": [{"type": "information", "scripts": {}, "variableReplacementStrategy": "originalfirst", "marks": 0, "prompt": "

Here we are using the following log laws

\n

\\[\\log_b(a)-\\log_b(c)=\\log_b\\left(\\frac{a}{c}\\right).\\]

\n

\\[\\log_b(a)+\\log_b(c)=\\log_b(ac)\\]

\n

Notice, all the bases are the same. 

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$\\log_\\var{b1}(\\var{10*arg})-\\log_\\var{b2}(\\var{arg})$ is equal to 

\n

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Here we are using the following log law

\n

\\[\\log_b(a)-\\log_b(c)=\\log_b\\left(\\frac{a}{c}\\right).\\]

\n

Notice, all the bases are the same. Also, notice how division inside the log becomes subtraction outside the log. 

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$\\log_{\\var{b1}}(10)$

", "

$\\log_{\\var{b2}}(10)$

", "

$\\log_{\\var{b1*b2}}(10)$

", "

$\\log_{\\var{b1+b2}}(10)$

", "

$\\log_{\\var{b1-b2}}(10)$

", "

None of the other options 

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