((3-x)分之x+3)+(x方+6x+9)分之(x方-9)
问题描述:
((3-x)分之x+3)+(x方+6x+9)分之(x方-9)
答
((3-x)分之x+3)+(x方+6x+9)分之(x方-9)
=(3-x)/(x+3)+(x+3)^2/(x-3)(x+3)
=(3-x+x+3)/(x+3)
=6/(x+3)