高中对数运算求出(lg5)^2+lg2*lg50的值,

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高中对数运算求出(lg5)^2+lg2*lg50的值,
高中对数运算
求出(lg5)^2+lg2*lg50的值,

高中对数运算求出(lg5)^2+lg2*lg50的值,
(lg5)^2+lg2*lg50
=lg5*lg5+lg2(lg10+lg5)
=lg5*lg5+lg2*1+lg2*lg5
=lg5(lg2+lg5)+lg2
=lg5+lg2
=1

(lg5)^2+lg2*lg50=2lg5+2lg5=4lg5

(lg5)^2+lg2*lg50
=(lg5)^2+lg2(lg5+1)
=lg5(lg5+lg2)+lg2
=lg5+lg2
=1

(lg5)^2+lg2*lg50
=(lg5)^2+lg2*lg(5*10)
=(lg5)^2+lg2*(lg5+1)
=(lg5)^2+lg2*lg5+lg2
=lg5*(lg5+lg2)+1g2
=lg5*lg10+1g2
=lg5+lg2
=lg10
=1

lg50=lg25+lg2吧
lg25=2lg5
(lg5)^2+lg2*(2lg5+lg2)