| Exam Board | CAIE |
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| Module | P3 (Pure Mathematics 3) |
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| Year | 2017 |
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| Session | June |
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| Topic | Exponential Equations & Modelling |
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3 Using the substitution \(u = \mathrm { e } ^ { x }\), solve the equation \(4 \mathrm { e } ^ { - x } = 3 \mathrm { e } ^ { x } + 4\). Give your answer correct to 3 significant figures.