f(x)=f(1/x)lgx+1
令x=1/x
f(1/x)=f(x)lg1/x+1
f(x)=f(x)lg1/xlgx+1
f(10)=f(10)lg1/10lg10+1
f(10)=-f(10)+1
2f(10)=1
f(10)=1/2