C
chungthuychung


a)$x^2(x-1)^2+x(x^2-1)=2(x+1)^2$
b)$x^4+(x-1)(3x^2+2x-2)=0$
c)$(\frac{x+1}{x-2})^2 +\frac{x+1}{x-4}=12(\frac{x-2}{x-4})^2$
d)$2014(2015-2014x^2)^2=2015-x$
b)$x^4+(x-1)(3x^2+2x-2)=0$
c)$(\frac{x+1}{x-2})^2 +\frac{x+1}{x-4}=12(\frac{x-2}{x-4})^2$
d)$2014(2015-2014x^2)^2=2015-x$