Discussion: This student works out many, many cases and conjectures that the only prime p for which p^2 + 2 is prime is p = 3 since in all the other cases (primes p greater than 3) the result appears to be composite, specifically divisible by 3 and conjectures that this is so. Then, by using methods from number theory, the notion congruence modulo a natural number the student is able to demonstrate this.

Written response: Good investigation and conjecture. Nice use of number theory to prove this.

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