Question

下列說(shuō)法正確的是（　�。�

A．多項(xiàng)式乘以單項(xiàng)式，積可以是多項(xiàng)式也可以是單項(xiàng)式

B．多項(xiàng)式乘以單項(xiàng)式，積的次數(shù)等于多項(xiàng)式的次數(shù)與單項(xiàng)式次數(shù)的積

C．多項(xiàng)式乘以單項(xiàng)式，積的系數(shù)是多項(xiàng)式系數(shù)與單項(xiàng)式系數(shù)的和

D．多項(xiàng)式乘以單項(xiàng)式，積的項(xiàng)數(shù)與多項(xiàng)式的項(xiàng)數(shù)相等

 

Answer 1

【答案】

D

【解析】

試題分析：根據(jù)單項(xiàng)式乘以多項(xiàng)式的有關(guān)知識(shí)作答．

解：A、多項(xiàng)式乘以單項(xiàng)式，積一定是多項(xiàng)式，而不是單項(xiàng)式，故本選項(xiàng)錯(cuò)誤；

B、多項(xiàng)式乘以單項(xiàng)式，積的次數(shù)等于多項(xiàng)式的次數(shù)與單項(xiàng)式次數(shù)的和，故本選項(xiàng)錯(cuò)誤；

C、多項(xiàng)式乘以單項(xiàng)式，積的系數(shù)是多項(xiàng)式系數(shù)與單項(xiàng)式系數(shù)的積，故本選項(xiàng)錯(cuò)誤；

D、正確．

故選D．

考點(diǎn)：?jiǎn)雾?xiàng)式乘多項(xiàng)式．

點(diǎn)評(píng)：本題實(shí)際上考查了單項(xiàng)式乘以多項(xiàng)式的法則：?jiǎn)雾?xiàng)式與多項(xiàng)式相乘，就是根據(jù)分配律用單項(xiàng)式去乘多項(xiàng)式的每一項(xiàng)，再把所得的積相加．