您的位置: 首页  >  作业答案  >  其他  >  计算:(x-1)/(x^2 + 3x + 2) + 6/(2 + x - x^2) - (10-x)/(4-x^2)答案好象是0

计算:(x-1)/(x^2 + 3x + 2) + 6/(2 + x - x^2) - (10-x)/(4-x^2)答案好象是0

分类: 作业答案 • 2022-01-09 18:01:27
问题描述：

计算:(x-1)/(x^2 + 3x + 2) + 6/(2 + x - x^2) - (10-x)/(4-x^2)
答案好象是0

答

2(x-10)/((x-2)*(x+2))

答

(x-1)/(x^2 + 3x + 2) + 6/(2 + x - x^2) - (10-x)/(4-x^2)
=(x-1)/(x+1)(x+2)-6/(x-2)(x+1)-(10-x)/(x+2)(x-2)
=[(x-1)(x-2)-6(x+2)-(10+x)(x+1)]/(x+1)(x+2)(x-2)
=(x^2-3x+2-6x-12-10x-10-x^2-x)/(x+1)(x+2)(x-2)
=(-20-20x)/(x+1)(x+2)(x-2)
=-20(1+x)/(x+1)(x+2)(x-2)
=-20/(x+2)(x-2)

相关推荐