| Exam Board | Pre-U |
|---|---|
| Module | Pre-U 9794/1 (Pre-U Mathematics Paper 1) |
| Year | 2013 |
| Session | June |
| Marks | 4 |
| Topic | Exponential Equations & Modelling |
| Type | Simple exponential equation solving |
| Difficulty | Easy -1.2 This is a straightforward single-step exponential equation requiring only taking logarithms of both sides and dividing. It's a routine procedural question with no problem-solving element, making it easier than the average A-level question which typically involves multiple steps or techniques. |
| Spec | 1.06g Equations with exponentials: solve a^x = b |
Introduce logarithms — M1
Use power law — M1
Obtain $5x \ln 2 = \ln 15$ — A1
Obtain $x = 0.781$ — A1 **[4]**4 Solve the equation $2 ^ { 5 x } = 15$, giving the value of $x$ correct to 3 significant figures.
\hfill \mbox{\textit{Pre-U Pre-U 9794/1 2013 Q4 [4]}}