SOLUTION: Show that x^4 +(plus) 4 is prime only for one value of x,where x belongs to set of natural no.s

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Question 432964: Show that x^4 +(plus) 4 is prime only for one value of x,where x belongs to set of natural no.s
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!

For all natural numbers x+%3E=+2, each of the two factors above is a positive integer greater than 1, hence the number itself is composite. If x = 1, the number itself is 1%5E4+%2B+4+=+5, which is prime. The solution is complete.