Question

lg52+2/3lg8+lg5*lg20+(lg2)2 (lg2)2是(lg2)的平方 lg52是lg5的平方

Answer 1

(lg5)2+2/3lg8+lg5*lg20+(lg2)2

=(lg5)2+2lg2+lg5(lg5+2lg2)+(lg2)2

=(lg5)2+2lg5lg2+(lg2)2+2lg2+(lg5)2

=(lg5+lg2)2+2lg2+(lg5)2

=1+lg100lg2+(lg5)2

=1+(2lg5+lg2)lg2+(lg5)2

=1+(lg2)2+2lg5lg2+(lg5)2

=1+(lg2+lg5)2

=1+1

=2