函数f(x)=(ax+1)/(x+2)在区间(-2,+∞)上单调递增,则实数a的取值范围是( )f(x)=(ax+1)/(x+2)=a-(2a-1)/(x+ 资源ID: f(x)=(ax+1)/(x+2) =a-(2a-1)/(x+2)要使y=-(2a-1)/(x+2)在(-2,+∞)上单调递增,由于-1/(x+2)在(-2,+∞)上单调递增,所以只需令2a-1>0 即a>1/2所以a得取值范围为(1/2,+∞) (ax+1)/(x+2)=a+(-2a+1)/(x+2)因为(-2,+无穷)递增,所以-2a+1<0;a>1/2; ← 上一篇: 下一篇: →