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Selection of Quadratic Equations to Solve
"}, "statement": "Solve the following quadratic equations with the quadratic formula:
Worked example using Part a:
\nFind the roots of $\\simplify{{a[0]}*x^2+{b[0]}*x+{c[0]}}=0$.
\nThe quadratic formula is given by $x = \\dfrac{-b\\pm\\sqrt{b^2-4ac}}{2a}$
\nTo solve this, simply input the numbers from the equation into the formula, defining the coefficient of $x^2$ as $a$, the coefficient of $x$ as $b$, and the constant as $c$.
\nHere, $x=$
Inputting these figures into a calculator, starting with the minus sign before the root, gives: $x=\\var{ansmin}$,
\nand using the positive root version gives the other solution: $x=\\var{ansplus}$.
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", "precisionPartialCredit": "50", "minValue": "(-{b[0]}-sqrt({b[0]}^2-4*{a[0]}*{c[0]}))/(2*{a[0]})-0.0005"}, {"maxValue": "(-{b[0]}+sqrt({b[0]}^2-4*{a[0]}*{c[0]}))/(2*{a[0]})+0.0005", "precision": "4", "mustBeReducedPC": 0, "scripts": {}, "marks": 1, "correctAnswerStyle": "plain", "notationStyles": ["plain", "en", "si-en"], "mustBeReduced": false, "type": "numberentry", "variableReplacements": [], "precisionType": "sigfig", "strictPrecision": false, "allowFractions": false, "variableReplacementStrategy": "originalfirst", "showCorrectAnswer": true, "showPrecisionHint": false, "showFeedbackIcon": true, "correctAnswerFraction": false, "precisionMessage": "You have not given your answer to the correct number of significant figures.
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\nGive your answers in ascending order (ie smallest first) to four significant figures.
\n$x=$ [[0]] and $x=$ [[1]]
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\nGive your answers in ascending order to four significant figures.
\n$x=$ [[0]] and $x=$ [[1]]
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\nGive your answers in ascending order to four significant figures.
\n$x=$ [[0]] and $x=$ [[1]]
\n"}, {"variableReplacements": [], "scripts": {}, "marks": 0, "variableReplacementStrategy": "originalfirst", "showCorrectAnswer": true, "showFeedbackIcon": true, "gaps": [{"maxValue": "(-{b[3]}-sqrt({b[3]}^2-4*{a[3]}*{c[3]}))/(2*{a[3]})+0.0005", "precision": "4", "mustBeReducedPC": 0, "scripts": {}, "marks": "1", "correctAnswerStyle": "plain", "notationStyles": ["plain", "en", "si-en"], "mustBeReduced": false, "type": "numberentry", "variableReplacements": [], "precisionType": "sigfig", "strictPrecision": false, "allowFractions": false, "variableReplacementStrategy": "originalfirst", "showCorrectAnswer": true, "showPrecisionHint": false, "showFeedbackIcon": true, "correctAnswerFraction": false, "precisionMessage": "You have not given your answer to the correct precision.
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\nGive your answers in ascending order to four significant figures.
\n$x=$ [[0]] and $x=$ [[1]]
\n"}], "ungrouped_variables": ["a", "b", "c", "disc1", "disc2", "disc3", "disc4", "ansmin", "ansplus"], "type": "question", "contributors": [{"name": "Hannah Bartholomew", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/530/"}]}]}], "contributors": [{"name": "Hannah Bartholomew", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/530/"}]}