左=logx(2)*[2logx(2)]^2 =4log3x(2); 右=log8x(2) 则4log3x(2)=log8x(2); log5x(2)=4; logx(2)=2^(2/5); log2(x)=2^(-2/5); x=2^[2^(-2/5)];
