As a little diversion I thought i'd post this question which I call a forehead-slapper because that's what you'll likely do when you see the answer. You won't need more than high school maths to solve it.(adsbygoogle = window.adsbygoogle || []).push({});

Show that if x and [tex]x^2+8[/tex] are primes then so is [tex]x^3-8[/tex]

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# Forehead slapper #1

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