更新時(shí)間:2024-01-12 16:36:39作者:貝語網(wǎng)校
已知A是關(guān)于x的五次多項(xiàng)式,B是關(guān)于x的四次多項(xiàng)式,則多項(xiàng)式A+B的次數(shù)是________次,B-A的次數(shù)是________次.
5 5
本題涉及多項(xiàng)式考點(diǎn),解答時(shí)根據(jù)多項(xiàng)式的概念作出判斷.
解答:在A中x的次數(shù)最高為5,而在B中x的次數(shù)最高為4.由于在B中沒有關(guān)于x的五次單項(xiàng)式的同類項(xiàng),所以當(dāng)A+B、B-A時(shí),A中x的次數(shù)就不會(huì)改變,仍然為5.
點(diǎn)評(píng):解決此類題目的關(guān)鍵是熟記整式的加減只能是同類項(xiàng)間的加減,非同類項(xiàng)之間不能進(jìn)行合并.