2(lg√2)^2 +lg√2*lg5+(√(lg√2)^2-lg2+1)(lg√2)^2-lg2+1都是要开根号的·~

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2(lg√2)^2+lg√2*lg5+(√(lg√2)^2-lg2+1)(lg√2)^2-lg2+1都是要开根号的·~2(lg√2)^2+lg√2*lg5+(√(lg√2)^2-lg2+1)(lg√2

2(lg√2)^2 +lg√2*lg5+(√(lg√2)^2-lg2+1)(lg√2)^2-lg2+1都是要开根号的·~
2(lg√2)^2 +lg√2*lg5+(√(lg√2)^2-lg2+1)
(lg√2)^2-lg2+1
都是要开根号的·~

2(lg√2)^2 +lg√2*lg5+(√(lg√2)^2-lg2+1)(lg√2)^2-lg2+1都是要开根号的·~
lg√2=(1/2)lg2
lg5=1-lg2
所以原式=2*(1/4)(lg2)^2+(1/2)lg2(1-lg2)+√[(1/4)*(lg2)^2-lg2+1]
=(1/2)(lg2)^2+(1/2)lg2-(1/2)(lg2)^2+(1/2))*√[(lg2)^2-4lg2+4]
=(1/2)lg2+(1/2)√(1-lg2)^2
=(1/2)lg2+(1/2)*(1-lg2)
=(1/2)lg2+(1/2)-(1/2)lg2
=1/2