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anthony3894
Factor completely p4 – 8p2 + 16
http://www.wolframalpha.com/input/?i=p%5E4+%E2%80%93+8p%5E2+%2B+16
It's always good to let p^2 = x, then you'll have x^2 - 8x + 16 Which is much simpler to factor. After factoring, simply replace x with p^2