用反证法.设p(x)是数域F上的不可约多项式.假设a是p(x) (在复数域内)的重根,则有p(a) = 0,p'(a) = 0 (p'(x)为p(x)求导得到的多项式).若p(x)与p'(x)互素,则存在u(x),v(x) ∈ F[x]使得u(x)p(x)+v(x)p'(x) = 1,代入x = a...