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问题: 指对数化简1

1)(lg5)^2+lg2*lg50=
2)lg5(lg8+lg1000)+(lg2^√3)^2+lg1/6+lg0.06=
3)(log3^2+log9^2)(log4^3+log8^3)=

解答:

1)(lg5)^2+lg2*lg50
=(lg5)^2+lg2*lg(5^2*2)
=((lg5)^2+lg2(2lg5+lg2)
=(lg5)^2+2lg5lg2+(lg2)^2
=(lg5+lg2)^2
=(lg10)^2
=1^2=1.
2)lg5(lg8+lg1000)+[lg(2^√3)]^2+lg(1/6)+lg0.06
=lg5(3lg2+3)+(√3*lg2)^2+(-lg6)+(lg6-lg100)
=3lg2lg5+3lg5+3(lg2)^2-2
=3lg2(lg5+lg2)+3lg5-2
=3lg2lg10++3lg5-2
=3(lg2+lg5)-2
=3lg10-2=3-2=1.
3)(log_3_2+log_9_2)(log_4_3+log_8_3) 分别换成底数是2的对数
=(1/log3+1/log9)(log3/log4+log3/log8) 并且省略底数2.
=[1/log3+(1/2)/log3]*[(1/2)log3+(1/3)log3]
=(3/2)/log3*(1/6)log3
=3/2*1/6
=1/4.
=