计算:(x²-2x-8)分之(2-x)+(3x+6)分之(x+4)

问题描述:

计算:(x²-2x-8)分之(2-x)+(3x+6)分之(x+4)

解原式=3(2-x)/3(x-4)(x+2)+(x+4)(x-4)/3(x+2)(x-4)=(6-3x)/3(x-4)(x+2)+(x²-16)/3(x+2)(x-4)=(6-3x+x²-16)/3(x+2)(x-4)=(x²-3x-10)/3(x+2)(x-4)=(x-5)(x+2)/3(x+2)(x-4)=(x-5)/3(x-4)