| Exam Board | OCR MEI |
|---|---|
| Module | C4 (Core Mathematics 4) |
| Year | 2014 |
| Session | June |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Generalised Binomial Theorem |
| Type | Form (a+bx)^n requiring factorisation |
| Difficulty | Moderate -0.3 This is a straightforward application of the binomial expansion formula for fractional powers, requiring students to substitute into the standard formula and simplify three terms. The validity condition (|x/4| < 1) is a standard bookwork result. While it requires careful algebraic manipulation, it's a routine C4 question with no problem-solving element beyond direct application of a learned technique. |
| Spec | 1.04c Extend binomial expansion: rational n, |x|<11.04d Binomial expansion validity: convergence conditions |
Find the first three terms in the binomial expansion of $(4+x)^{\frac{1}{2}}$. State the set of values of $x$ for which the expansion is valid. [5]
\hfill \mbox{\textit{OCR MEI C4 2014 Q2 [5]}}