Question

5個(gè)非零實(shí)數(shù)相乘，結(jié)果為負(fù)，則負(fù)因數(shù)的個(gè)數(shù)為（　�。�

A．1個(gè)

B．3個(gè)

C．5個(gè)

D．1個(gè)或3個(gè)或5個(gè)

Answer 1

分析：根據(jù)有理數(shù)的乘法的運(yùn)算法則解答．

解答：解：∵5個(gè)非零實(shí)數(shù)相乘，結(jié)果為負(fù)，
∴負(fù)因數(shù)的個(gè)數(shù)為1個(gè)或3個(gè)或5個(gè)．
故選D．

點(diǎn)評：本題考查了有理數(shù)的乘法，幾個(gè)不等于零的數(shù)相乘，積的符號由負(fù)因數(shù)的個(gè)數(shù)決定：當(dāng)負(fù)因數(shù)有奇數(shù)個(gè)數(shù)，積為負(fù)；當(dāng)負(fù)因數(shù)的個(gè)數(shù)為偶數(shù)個(gè)時(shí)，積為正．