// Numbas version: exam_results_page_options {"name": "Calculating powers (-a^(-1))", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variable_groups": [], "variablesTest": {"maxRuns": 100, "condition": "a<>b"}, "parts": [{"variableReplacementStrategy": "originalfirst", "type": "gapfill", "variableReplacements": [], "scripts": {}, "showCorrectAnswer": true, "marks": 0, "showFeedbackIcon": true, "prompt": "

$-\\var{a}^{-1}=\\ $ 1[[0]].

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The correct calculation is $-\\var{a}^{-1}=-\\dfrac{1}{\\var{a}^1}=-\\dfrac{1}{\\var{a}}=\\dfrac{1}{\\boxed{-\\var{a}}}$.

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Remember that any number raised to the power 1 is just the number itself.

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This question tests a student's ability to raise a negative base to an exponent of -1.

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This is the absolute value of the exponent.

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This is the base.

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Calculate the following power.

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If you think the answer should be negative then a negative sign should be entered in the denominator.

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", "name": "Calculating powers (-a^(-1))", "type": "question", "contributors": [{"name": "Anthony Brown", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/799/"}]}]}], "contributors": [{"name": "Anthony Brown", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/799/"}]}