differentiate and find the cordinates of 2x/(1+x^2)^2
hmmm. odd question since
2/(1+x^2)^2 is the derivative of -1/(1+x^2)
But, assuming that's what you want, we get
-2(3x^2-1)/(1+x^2)^3
No idea what you want when you say "find the cordinates[sic]" of that.