Cho biểu thức A = (1/1 - x - /1+ x): (1/ 1- x + 1/1 + x) + 1/ x - 1 a) Rút gọn biểu thức
Giải thích
a) A =11−x−11+x:11−x+11+x+1x−1
=1+x−1−x1−x1+x:(1+x)+(1−x(1−x)(1+x)+1x−1=1+x−1+x(1−x)(1+x).(1−x)(1+x)1+x+1−x+1x−1=2x2+1x−1=x+1x−1=x2−x+1x−1
a) A =11−x−11+x:11−x+11+x+1x−1
=1+x−1−x1−x1+x:(1+x)+(1−x(1−x)(1+x)+1x−1=1+x−1+x(1−x)(1+x).(1−x)(1+x)1+x+1−x+1x−1=2x2+1x−1=x+1x−1=x2−x+1x−1