若函数f(x)=(2-ax)/(3x+5)的值域为(-无穷,1)∪(1,+无穷),则a的值

问题描述:

若函数f(x)=(2-ax)/(3x+5)的值域为(-无穷,1)∪(1,+无穷),则a的值

解由f(x)=(2-ax)/(3x+5)=(2-1/3a*3x)/(3x+5)=[2-1/3a(3x+5)-5/3a]/(3x+5)=[-(1/3)a(3x+5)+2-5/3a]/(3x+5)=-(1/3)a+(2-5/3a)/(3x+5)即y≠-(1/3)a由函数的值域为(-无穷,1)∪(1,+无穷),即函数...