| Exam Board | CAIE |
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| Module | P1 (Pure Mathematics 1) |
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| Year | 2013 |
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| Session | June |
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| Topic | Product & Quotient Rules |
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6 The non-zero variables \(x , y\) and \(u\) are such that \(u = x ^ { 2 } y\). Given that \(y + 3 x = 9\), find the stationary value of \(u\) and determine whether this is a maximum or a minimum value.