关于整系数多项式的一个结果

A result on the polynomial with integral coefficients

用简洁的方法 ,证明了如下结果 :若整系数多项式 f (x) =xn +a1xn- 1+a2 xn- 2 +… +an- 1x +an的所有根的绝对值都不大于 1 ,an≠ 0 ,则 f (x)

The author proved briefly that if f(x)=x n+a 1x n-1 +a 2x n-2 +...+a n-1 x+a n (a n≠0) is a polynomial with integral coefficients,and α is any root of f(x), |α|≤1,then α is a unit root.