lg5*lg8000+（lg2^根号3）^2=lg5*(lg8+lg1000)+(√3*lg2)^2=lg5*(3lg2+3)+3*(lg2)^2=3lg2*lg5+3lg5+3(lg2)^2=3lg2(lg2+lg5)+3lg5=3lg2*lg10+3*lg5=3lg2+3lg5=3(lg2+lg5)=3*1=3