SOLUTION: If a & b are two odd prime numbers, show that a^2-b^2 is composite.

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Question 738231: If a & b are two odd prime numbers, show that a^2-b^2 is composite.
Answer by MathLover1(20850) About Me  (Show Source):
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Assume p > q. Since p, q are both odd, p - q ≥ 2. Also, q ≥ 3, p ≥ 5.
Since p² - q² = (p + q) (p - q) where p + q, where p + q > p ≥ 5, and p - q ≥ 2, p² - q² is composite.