Question

若干個不等于0的有理數(shù)相乘，積的符號

1. A.
   由因數(shù)的個數(shù)決定
2. B.
   由正因數(shù)的個數(shù)決定
3. C.
   由負(fù)因數(shù)的個數(shù)決定
4. D.
   由負(fù)因數(shù)和正因數(shù)個數(shù)的差為決定

Answer 1

C
分析：可根據(jù)有理數(shù)乘法運(yùn)算的符號法則進(jìn)行判斷．
解答：幾個不等于零的數(shù)相乘，積的符號由負(fù)因數(shù)的個數(shù)決定．
當(dāng)負(fù)因數(shù)有奇數(shù)個數(shù)，積為負(fù)；當(dāng)負(fù)因數(shù)的個數(shù)為偶數(shù)個時，積為正．
故選C．
點(diǎn)評：本題考查了有理數(shù)的乘法法則：幾個不等于0的數(shù)相乘，積的符號由負(fù)因數(shù)的個數(shù)決定．當(dāng)負(fù)因數(shù)有奇數(shù)個時，積為負(fù)；當(dāng)負(fù)因數(shù)有偶數(shù)個時，積為正．