1.（lg5）2次方+lg2*lg50

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1.（lg5）2次方+lg2*lg50
(lg5)²+lg2*lg50
=(lg5)²+lg2x(lg5*5*2)
=(lg5)²+lg2x(lg5+lg5+lg2)
=(lg5)²+2lg2lg5+（lg2）²
=（lg5+lg2)²
=（lg10）²
=1²
=1======以下答案可供参考======
供参考答案1:
lg2+lg5=lg(2*5)=lg10=1
lg2*lg50=lg2*lg(5*10)=lg2*(lg5+lg10)=lg2*lg5+lg2
(lg5)^2+lg2*lg5+lg2=lg5*(lg2+lg5)+lg2=lg5+lg2=1