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$x$ is a sequence between -2 and 10.
\n$z$ selects the values from $x$ that are greater than or equal to 7.
\n$y$ selects the values from $x$ that are greater than or equal to 7 OR less than 0.
\n$a$ selects the elements of $y$ that are equal to -2. So if $y$ = -2 -1 7 8 9 10 it is the first element that is equal to -2.
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7 8 9 10
", "0 1 2 3 4 5 6
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What is the value of $y$?
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7 8 9 10
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> x = seq(-2, 10)", "variable_groups": [], "variablesTest": {"maxRuns": 100, "condition": ""}, "variables": {}, "metadata": {"description": "", "licence": "Creative Commons Attribution 4.0 International"}, "type": "question", "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}], "contributors": [{"name": "Amy Chadwick", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/505/"}]}]}], "contributors": [{"name": "Amy Chadwick", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/505/"}]}
> z = x[(x >= 7) ]
> y = x[(x >= 7) | x < 0]
> a = which(y==-2)