Question

對(duì)于單項(xiàng)式-2³x²y²z的系數(shù)、次數(shù)說法正確的是（　�。�

A．系數(shù)為-2，次數(shù)為8

B．系數(shù)為-8，次數(shù)為5

C．系數(shù)為-2³，次數(shù)為4

D．系數(shù)為-2，次數(shù)為7

Answer 1

分析：根據(jù)單項(xiàng)式系數(shù)、次數(shù)的定義來求解．單項(xiàng)式中數(shù)字因數(shù)叫做單項(xiàng)式的系數(shù)，所有字母的指數(shù)和叫做這個(gè)單項(xiàng)式的次數(shù)．

解答：解：根據(jù)單項(xiàng)式系數(shù)、次數(shù)的定義，單項(xiàng)式-2³x²y²z的數(shù)字因數(shù)是-2³，=-8，所有字母的指數(shù)和為2+2+1=5．
故選：B．

點(diǎn)評(píng)：此題考查的知識(shí)點(diǎn)是單項(xiàng)式，確定單項(xiàng)式的系數(shù)和次數(shù)時(shí)，把一個(gè)單項(xiàng)式分解成數(shù)字因數(shù)和字母因式的積，是找準(zhǔn)單項(xiàng)式的系數(shù)和次數(shù)的關(guān)鍵．