Question

log2x-3logx2=-2

Answer 1

问：log2x-3logx2=-2

答：lgx/lg2-3lg2/lgx=-2(lgx)^2-3(lg2)^2+2lg2* lgx=0(lgx-lg2)*(lgx+3lg2)=0lgx=lg2解得x=2或lgx+lg2=0解得x=1/2

答：您好，解原式=lgx/lg2-3lg2/lgx=-2(lgx)^2-3(lg2)^2+2lg2* lgx=0(lgx-lg2)*(lgx+3lg2)=0lgx=lg2解得x=2或lgx+lg2=0解得x=1/2即x=2或ⅹ=1/2

问：这个19题方便解一下吗

答：19题) f(x)= Asin( ωx+ ψ)(A>0，ω>0，|Ψ丨≤π/2M(1,根号3)当ⅹ=1时f(x)= Asin(ω+ψ)

问：？

答：19题) f(x)= Asin( ωx+ ψ)(A>0，ω>0，|Ψ丨≤π/2M(1,根号3)当ⅹ=1时f(x)= Asin(ω+ψ)=根号3，

答：你能把19题图片完整的发过来吗

答：19题) f(x)= Asin( ωx+ ψ)= (A>0，ω>0，|Ψ丨≤π/2M(1,根号3)当ⅹ=1时f(x)= Asin(ω+ψ)=根号3，A=根号3ω+Ψ=π/2①当x=5时5ω+ψ=3π/2②②-①得4ω=πω=π/4Ψ=π/2-π/4=π/4解析式为f(x)=根号3sin(πⅹ/4+π/4

答：(2) g(x)= f(x/π)=根号3sin(x/4+π/4)y= g(x)+g(2π/3+x)=根号3sin(x/4+π/4)+根号3sin(x/4+5π/12)

答：19题) (1)f(x)= Asin( ωx+ ψ)= (A>0，ω>0，|Ψ丨≤π/2M(1,根号3)当ⅹ=1时f(x)= Asin(ω+ψ)=根号3，A=根号3ω+Ψ=π/2①当x=5时5ω+ψ=3π/2②②-①得4ω=πω=π/4Ψ=π/2-π/4=π/4解析式为f(x)=根号3sin(πⅹ/4+π/4)

答：(2) g(x)= f(x/π)=根号3sin(x/4+π/4)y= g(x)+g(2π/3+x)=根号3sin(x/4+π/4)+根号3sin(x/4+5π/12)在x∈(-π，π)上-π/4+π/4=0-π/4+5π/12=π/6π/4+π/4=π/2π/4+5π/12=8π/12=2π/3

答：(π/2-5π/12)x4=2π/3在(-π，2π/3)上y= g(x)+ g(2π/3+ x)是增函数

答：(2) g(x)= f(x/π)=根号3sin(x/4+π/4)y= g(x)+g(2π/3+x)=根号3sin(x/4+π/4)+根号3sin(x/4+5π/12)在x∈(-π，π)上-π/4+π/4=0-π/4+5π/12=π/6π/4+π/4=π/2π/4+5π/12=8π/12=2π/3(π/2-5π/12)x4=2π/3sin(x/4+π/4)在区间(-π，π)上单调增sin(x/4+5π/12)在区间(-π，2π/3]上单调增在(-π，2π/3]上y= g(x)+ g(2π/3+ x)是增函数即y= g(x)+ g(2π/3+ x)单调增区间(-π，2π/3]

答：补充-下，增函数+增函数=增函数，增函数-减函数=增函数，减函数+减函数=减函数，减函数-增函数=减函数。而增函数+减函数的增减性不一定的。

答：明白了吗？亲