| Exam Board | OCR MEI |
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| Module | C3 (Core Mathematics 3) |
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| Year | 2013 |
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| Session | January |
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| Topic | Proof |
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7
- Disprove the following statement:
$$3 ^ { n } + 2 \text { is prime for all integers } n \geqslant 0 .$$
- Prove that no number of the form \(3 ^ { n }\) (where \(n\) is a positive integer) has 5 as its final digit.