Môn Toán Lớp 8: `(x + 1)/(x^2 + x + 1)` `-` `(x – 1)/(x^2 – x + 1)` = `3/[x(x^4 + x^2 + 1)]`

(x+1)/(x^2+x+1) – (x-1)/(x^2-x+1)=3/(x(x^4+x^2+1))
((x+1)(x^2-x+1))/((x^2+x+1)(x^2-x+1)) – ((x-1)(x^2+x+1))/((x^2-x+1) (x^2+x+1))=3/(x(x^4+x^2+1))            
(x^3+1)/((x^2+x+1)(x^2-x+1)) – (x^3-1)/((x^2+x+1)(x^2-x+1))=3/(x(x^4+x^2+1))
(x^3+1-(x^3-1))/((x^2+x+1)(x^2-x+1))=3/(x(x^4+x^2+1))
(x^3+1-x^3+1)/((x^2+x+1)(x^2-x+1))=3/(x(x^4+x^2+1))
2/((x^2+x+1)(x^2-x+1))=3/(x(x^4+x^2+1))
(2x)/(x(x^2+x+1)(x^2-x+1))=3/(x(x^4+2x^2+1-x^2)
(2x)/(x(x^2+x+1)(x^2-x+1))=3/(x[(x^2+1)^2-x^2]
(2x)/(x(x^2+x+1)(x^2-x+1))=3/(x(x^2+x+1)(x^2-x+1))
(2x)/(x(x^2+x+1)(x^2-x+1))-3/(x(x^2+x+1)(x^2-x+1))=0
(2x-3)/(x(x^2+x+1)(x^2-x+1)=0
2x-3=0=>x=3/2