函数超难练习卷子 球解析 21.计算(1)log2.5 6.25+lg(1/100)+In√e+2^(log2 3)(2

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  • 21.计算

    (1)log2.5 6.25+lg(1/100)+In√e+2^(log2 3)

    =2-2+1/2+3=7/2

    (2)lg25+lg2 lg50+(lg2)^2

    =lg25+lg2lg(100/2)+lg²2

    =lg25 +lg2(2-lg2)+lg²2

    =lg25+2lg2-lg²2+lg²2

    =lg25+lg4=lg100=2

    (3)(lg(1/4)-lg25)+100^-1/2

    =(-lg4-lg25)+1/10

    =-lg100+1/10=-2+1/10

    (4)(log3 2+log9 2)×(log4 3+log8 3)

    =[log(3)2+1/2log(3)2]×(1/2log(2)3+1/3log(2)3]

    =3/2 [log(3)2]×5/6×log(2)3=3/2*5/6=5/4

    (5)(0.027)^1/3-(1/7)^-2+(25/9)^1/2-((√2)-1)^0

    =3/10-49+5/3-1 (后面你自己算吧)

    (6)(lg2)^2+lg2 ×(lg5+log3 5)/(log3 10)

    =(lg2)^2+lg2 ×(lg5+lg5/lg3)lg3

    =(lg2)^2+lg2 ×(lg5lg3+lg5)

    好奇怪,错了吧

    6) (lg2)^2+lg2 ×lg5+log3 5/(log3 10)

    =(lg2)^2+lg2 ×lg5+lg5/lg3*lg3

    =(lg2)^2+lg2 ×lg5+lg5

    =lg2(lg2+lg5)=lg5

    =lg2+lg5=lg10=1