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logx为底的2乘以log2x为底的4=log8x为底的2答案是x=8或者x=1/4

题目详情
logx为底的2乘以 log2x为底的4=log8x为底的2
答案是x=8 或者x=1/4
▼优质解答
答案和解析
log2^2/log2^x*log2^4/log2^(2x)=log2^2/log2^(8x)
2(3+log2^x)=log2^x*(1+log2^x)
6+2log2^x=log2^x+(log2^x)^2
(log2^X)^2-log2^x-6=0
[(log2^x)+2][(log2^x)-3]=0
log2^x+2=0,log2^x-3=0
log2^x=-2,log2^x=3
x=2^(-2)=1/4,x=2^3=8