f(1-x)=4^(1-x)/(4^(1-x)+2)=4/(4+2*4^x)=2/(2+4^x)f(x)+f(1-x)=4^x/(4^x+2)+2/(4^x+2)=(4^x+2)/(4^x+2)=1f（1/11）+f（2/11）+******+f（10/11）=[f(1/11)+f(10/11)]+...+[f(5/11)+f(6/11)]=1+1+1+1+1=5
