1.计算:lg 25+2/3lg 8+lg 5×lg 20+lg^(2) 2
来源:学生作业帮 编辑:搜搜考试网作业帮 分类:数学作业 时间:2024/04/29 14:19:21
1.计算:lg 25+2/3lg 8+lg 5×lg 20+lg^(2) 2
2.已知f(x)是一次函数,且满足3f(x+1)-2f(x-1)=2x+17,求f(x).
2.已知f(x)是一次函数,且满足3f(x+1)-2f(x-1)=2x+17,求f(x).
1,lg25+2/3lg8+lg5*lg20+lg^22
=2lg5+2lg2+lg5*(2lg2+lg5)+lg2*lg2
=2(lg5+lg2)+(lg5)^2+2lg2*lg5+(lg2)^2
=2lg10+(lg5+lg2)^2
=2+1^2
=3
2,设f(x)=ax+b
3f(x+1)-2f(x-1)
=3a(x+1)+3b-[2a(x-1)+2b]
=3ax+3a+3b-2ax+2a-2b
=ax+5a+b
=2x+17
所以,a=2
5a+b=17,b=7
f(x)=2x+7
=2lg5+2lg2+lg5*(2lg2+lg5)+lg2*lg2
=2(lg5+lg2)+(lg5)^2+2lg2*lg5+(lg2)^2
=2lg10+(lg5+lg2)^2
=2+1^2
=3
2,设f(x)=ax+b
3f(x+1)-2f(x-1)
=3a(x+1)+3b-[2a(x-1)+2b]
=3ax+3a+3b-2ax+2a-2b
=ax+5a+b
=2x+17
所以,a=2
5a+b=17,b=7
f(x)=2x+7
求值 lg 2lg 50 + lg 5lg 20 - lg 100lg 5lg 2
高一对数运算:计算lg^3(2)+lg^3(5)+3lg(2)lg
求值(lg 2)^2 lg 2lg 5 lg 50
计算:lg³2+lg³5+3lg2lg5
lg
不等式lg(x-3)+lg(x-2)
计算:lg(1/2)-lg(5/8)+lg(12.5)+log2为底3*log3为底8=
计算lg²5+lg2·lg25+lg²2
2lg²2+lg²5+3lg2lg5-lg2
问条对数计算题(lg 2)^2+lg 5*lg 20 -1=?
lg5²+lg4+lg 5×lg 20+(lg 2)²是多少 ,
lg(2-x)-lg(x-1)>0