Question

求函数y=x2+4/x2-1的值域?

Answer 1

请问分子是x2+4还是4若是x2+4则y=（x²-1+5）/(x²-1)=1+5/(x²-1)当x²在[0,1）上时y属于（负无穷,-4】当x²>1 y>1∴y属于（负无穷,-4】并上y>1若分子是4则y=（x²-1）+4/(x²-1)+1令t...