计算x^2-2x+1/2x^2-18除3-3x/4x^2-12x初三
问题描述：
计算x^2-2x+1/2x^2-18除3-3x/4x^2-12x初三
答
原式=(x-1)²/2(x²-9)÷[-3(x-1)/4x(x-3)]
=(x-1)²/2(x+3)(x-3)×[-4x(x-3)/3(x-1)]
=-2x(x-1)/3(x+3)
=(2x-2x²)/(3x+9)