Thực hiện các phép tính sau: b) 2x-1/ x+ 1-x/ 2x+1+ 3/ x^2-9+ 1-2x/ x+ x-1/ 2x+1- 3/ x+3.
Giải thích
b,2x−1x+1−x2x+1+3x2−9+1−2xx+x−12x+1−3x+3
=2x−1x+1−2xx+1−x2x+1+x−12x+1+3x2−9−3x+3=2x−1+1−2xx+1−x+x−12x+1+3−3(x−3)(x−3)(x+3)=0+0+−3x+12(x−3)(x+3)=−3x+12x2−9