Question

函数y=(x^2)/(x^2+1)(x∈R)的值域是

Answer 1

超级简单的问题,11）y=x^2/(x^2+1)=(x^2+1-1)/(x^2+1)=1-1/(x^2+1),由于0<1/(x^2+1)≤1,则1-1/(x^2+1)∈[0,1）,你求对了.12）用根的判别式法求将函数化为Ax^2+Bx+C=0的形式,即化得：(y-1)x^2-(y+a)x+(y+2)=0由于...