Question

6．若不等式組$\left\{\begin{array}{l}{x＜1}\\{x＞m-1}\end{array}\right.$恰有兩個整數(shù)解，則m的取值范圍是（　�。�

• A． -1≤m＜0
• B． -1＜m≤0
• C． -1≤m≤0
• D． -1＜m＜0

Answer 1

分析 先求出不等式的解集，根據(jù)題意得出關(guān)于m的不等式組，求出不等式組的解集即可．

解答 解：∵不等式組$\left\{\begin{array}{l}{x＜1}\\{x＞m-1}\end{array}\right.$的解集為m-1＜x＜1，
又∵不等式組$\left\{\begin{array}{l}{x＜1}\\{x＞m-1}\end{array}\right.$恰有兩個整數(shù)解，
∴-2≤m-1＜-1，
解得：-1≤m＜0
恰有兩個整數(shù)解，
故選A．

點評 本題考查了解一元一次不等式組，不等式組的解集的應(yīng)用，解此題的關(guān)鍵是能求出關(guān)于m的不等式組，難度適中．