(2x-3/x)^2+5+12x=18/x; 展开整理：4x^4+12x^3-7x^2-18x+9=0;(x-1)(4x^3+16x^2+9x-9)=0;(x-1)(x+3)(4x^2+4x-3)=0;(x-1)(x+3)(2x-1)(2x+3)=0;解得：x=1或x=-3或x=1/2或x=-2/3.[可能一步步比较麻烦,自己想只能到这步了...