Prove that the discriminant of f(x)=xn+nxn−1+n(n−1)xn−2+⋯+n(n−1)…(3)(2)x+n! is (−1)n(n−1)/2(n!)n.
So far, I let α1,…,αn be the roots of f(x). Taking the derivative of logf(x)=∑ni=1log(x−αi), we have that f′(x)f(x)=∑i=11x−αi. Thus, f′(αj)=n∏i=1,i≠j(αj−αi) Then the discriminant is $$D = \prod_{i
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