定义域:1+2^x不等于0(对任意实数均成立)
所以定义域为{x/x∈R}
值域:f(x)=(a+1-1-2^x)/(1+2^x)
=(a+1)/(1+2^x) -(1+2^x)/(1+2^x)
=(a+1)/(1+2^x) -1
当a>=-1即a+1>=0,0=
定义域:1+2^x不等于0(对任意实数均成立)
所以定义域为{x/x∈R}
值域:f(x)=(a+1-1-2^x)/(1+2^x)
=(a+1)/(1+2^x) -(1+2^x)/(1+2^x)
=(a+1)/(1+2^x) -1
当a>=-1即a+1>=0,0=