f(x)=(ax+2a-2a+1)/(x+2)=(ax+2a)/(x+2)+(1-2a)/(x+2)=a+(1-2a)/(x+2)则(1-2a)/(x+2)在x>-2递增所以1-2a是负数所以1-2a<0a>1/2
y=(ax+1)/(x+2)=a+(-2a+1)/(x+2)即y=(-2a+1)/x在(0,正无穷)递增即-2a+1＜0a＞1/2
