lg5^2+2/3lg8+lg5*lg20+lg2^2

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lg5^2+2/3lg8+lg5*lg20+lg2^2lg5^2+2/3lg8+lg5*lg20+lg2^2lg5^2+2/3lg8+lg5*lg20+lg2^2=lg5²+2lg2+lg5

lg5^2+2/3lg8+lg5*lg20+lg2^2
lg5^2+2/3lg8+lg5*lg20+lg2^2

lg5^2+2/3lg8+lg5*lg20+lg2^2
=lg5²+2lg2+lg5lg20+lg²2 后面的一个应该是lg²2
=2lg5+2lg2+(1-lg2)(1+lg2)+lg²2
=2(lg5+lg2)+1-lg²2 +lg²2
=2+1
=3

原式=lg5^2+2/3*lg2^3+lg5*lg(5*2^2)+lg2^2
=2lg5+2lg2+lg5*(lg5+2lg2)+2lg2
=2(lg5+lg2)+(lg5)^2+2lg5*lg2+2lg2
=2lg10+(lg5)^2+2lg5*lg2+2lg2
=2+(lg5)^2+2lg5*lg2+2lg2
=[(lg5)^2+2lg5*lg2+(lg...

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原式=lg5^2+2/3*lg2^3+lg5*lg(5*2^2)+lg2^2
=2lg5+2lg2+lg5*(lg5+2lg2)+2lg2
=2(lg5+lg2)+(lg5)^2+2lg5*lg2+2lg2
=2lg10+(lg5)^2+2lg5*lg2+2lg2
=2+(lg5)^2+2lg5*lg2+2lg2
=[(lg5)^2+2lg5*lg2+(lg2)^2]-(lg2)^2+2lg2+2
=(lg5+lg2)^2-(lg2)^2+2lg2+2
=(lg10)^2-(lg2)^2+2lg2+2
=1^2-(lg2)^2+2lg2+2
=-(lg2)^2+2lg2+1
=-(lg2-1)^2+2

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