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lg25+lg2*lg50+^2怎么计算

lg25+lg2*lg50+(lg2)^2 =2*lg5+lg2*(lg50+lg2) =2*lg5+lg2*lg100 =2*lg5+2*lg2 =2*(lg5+lg2) =2*lg10 =2

等于2

解:因为lg2+lg5=lg2*5=lg10=1,所以lg5=1-lg2 原式=lg(5^2)+lg2*lg(10*5)+lg2*lg2 =2*lg5+lg2(1+lg5)+lg2*lg2 =(lg2)^2+lg2*lg5+2lg5+lg2 =(lg2)^2+lg2*(1-lg2)+2(1-lg2)+lg2 =2 [√(lg^3-lg9+1)*(lg√27+lg8-lg√1000)]/(lg0.3)*(lg1.2)={√(lg...

原式=lg25+lg2(lg50+lg2) =lg25+lg2*2 =lg25+lg4 =lg100 =2

写成式子: lg2×lg2+lg50×lg4+lg4+lg5×lg5+lg25 =lg2×lg2+lg(2×5^2)×lg(2^2)+lg(2^2)+lg5×lg5+lg(5^2) 由lg(a*b)=lga+lgb,lg(a^b)=blga得到 =lg2×lg2+(lg2+2lg5)×2lg2+2lg2+lg5×lg5+2lg5 =lg2*lg2+2lg2*lg2+4lg2*lg5+2lg2+lg5*lg5+2lg5 =3(lg2...

=lg2(lg2+lg50)+lg25 =2lg2+lg25 =2

(lg2) +lg2·lg50+lg25= =(lg2) +lg2·(1+lg5)+2lg5 =(lg2) +lg2lg5+lg2+2lg5 =lg2(lg2+lg5)+lg2+2lg5 =lg2*lg10+lg2+2lg5 =lg2+lg2+2lg5 =2(lg2+lg5) =2lg10 =2

由题,lg5lg20-lg2lg50-lg25=lg5(2lg2+lg5)-lg2(2lg5+lg2)-2lg5=lg25-lg22-2lg5=lg5-lg2-2lg5=-(lg2+lg5)=-1故答案为-1

=lg100=2

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