Question

f((1-lnx)/(1+lnx))=xlnx求f(x)

Answer 1

令t=(1-lnx)/(1+lnx)

得lnx=(1-t)/(t+1)

x=e^[(1-t)/(t+1)]

所以f(t)=(1-t)/(t+1)*e^[(1-t)/(t+1)]

即f(x)=(1-x)/(1+x)*e^[(1-x)/(1+x)]