// Numbas version: finer_feedback_settings {"name": "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": [{"rulesets": {}, "preamble": {"js": "", "css": ""}, "tags": ["laws", "log laws", "logarithms", "logs", "rules"], "ungrouped_variables": ["num1", "num2", "ans1", "n1", "n2", "m1", "m2", "m3", "arg", "list", "b1", "b2"], "question_groups": [{"pickingStrategy": "all-ordered", "questions": [], "pickQuestions": 0, "name": ""}], "advice": "", "variable_groups": [], "variablesTest": {"maxRuns": 100, "condition": ""}, "parts": [{"scripts": {}, "variableReplacements": [], "prompt": "

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]]$\\large)$.

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

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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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Based on the definition of logarithms, determine the following:

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