| Exam Board | OCR MEI |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Year | 2012 |
| Session | January |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Topic | Trig Proofs |
| Type | Logical implication symbols (⇒, ⇔, ⇐) |
| Difficulty | Moderate -0.8 This question tests understanding of logical implication symbols rather than mathematical computation. Part (i) requires recognizing that odd cubes come from even bases (straightforward parity reasoning), and part (ii) involves understanding quadratic inequalities. While conceptual rather than computational, the logic is relatively accessible for C1 level, requiring only basic number properties and inequality analysis rather than complex proof techniques. |
| Spec | 1.01b Logical connectives: congruence, if-then, if and only if |
9 Complete each of the following by putting the best connecting symbol ( $\Leftrightarrow , \Leftarrow$ or ⇒ ) in the box. Explain your choice, giving full reasons.\\
(i) $n ^ { 3 } + 1$ is an odd integer □ $n$ is an even integer\\
(ii) $( x - 3 ) ( x - 2 ) > 0$ □ $x > 3$
Section B (36 marks)\\
\hfill \mbox{\textit{OCR MEI C1 2012 Q9 [4]}}