计算:x^-4/(x-2)(x-1)+x^-4/(x+2)(x+1)
问题描述:
计算:x^-4/(x-2)(x-1)+x^-4/(x+2)(x+1)
答
原式=(x+2)(x-2)/(x-2)(x-1)+(x+2)(x-2)/(x+2)(x+1)
=(x+2)/(x-1)+(x-2)/(x+1)
=(x²+3x+2+x²-3x+2)/(x+1)(x-1)
=(2x²+4)/(x²-1)