Question

函数y+=2x+-1/x+-1当x+≥2时函数值的取值范围

Answer 1

问：函数y+=2x+-1/x+-1当x+≥2时函数值的取值范围

答：亲 您好方法一:y=(2x-1)/(x-1)=[2(x-1)+1]/(x-1)=2+1/(x-1),由于1/(x-1)不=0,故得到y不=2,即Y的范围是(-无穷,2)U(2,+无穷)方法二:y(x-1)=2x-1yx-y=2x-1(y-2)x=y-1x=(y-1)/(y-2)所以有y-2不=0,即Y不=2.