lg √2 +lg10−2(lg √2 )^2−lg√ 2 •lg5.求值

lg √2 +lg10−2(lg √2 )^2−lg√ 2 •lg5.求值
lg √2 +lg10−2(lg √2 )^2−lg√ 2 •lg5.求值

lg √2 +lg10−2(lg √2 )^2−lg√ 2 •lg5.求值
=1/2 lg2+1-2(1/2lg2)²-1/2lg2×(1-lg2)
=1/2lg2 +1-1/2lg²1-1/2lg2+1/2lg²2
=1