f(x)g(x)的首项系数= f(x)的首项系数× g(x)的首项系数.3)运算律f(x)+ g(x) = g(x)+ f(x)(f(x)+ g(x)+h(x) = f(x)+(g(x)+ h(x)f(x)g(x) = g(x)f(x)(f(x)g(x)h(x) = f(x)(g(x)h(x)f(x)(g(x) + h(x) = f(x)g(x)+ f(x)h(x)f(x)g(x) = f(x)h(x), f(x) ± 0 = g(x) = h(x)81.2一元多项式F区区§1.2 一元多项式 f x g x ( ) ( ) 的首项系数 = f x( ) 的首项系数× g x( ) 的首项系数. 3) 运算律 f x g x g x f x ( ) ( ) ( ) ( ) + = + ( ( ) ( )) ( ) ( ) ( ( ) ( )) f x g x h x f x g x h x + + = + + f x g x g x f x ( ) ( ) ( ) ( ) = ( ( ) ( )) ( ) ( )( ( ) ( )) f x g x h x f x g x h x = f x g x h x f x g x f x h x ( )( ( ) ( )) ( ) ( ) ( ) ( ) + = + f x g x f x h x f x g x h x ( ) ( ) ( ) ( ), ( ) 0 ( ) ( ) =   =