y = (c+a-b)/(b-a)
z = ((d*(b+c))+(a*(e+f)))/(e+f)/(b+c)
a = ((((e^2)+d)*b*((b^2)+2))-e-f)/b/((b^2)+2)/(e+f)
a = ((b*((((e^2)+d)*((b^2)+2))+(b*(e+f))))+e+f)/(e+f)/b/((b^2)+2)
a = ((1/(x^(1+n)))+(1/(x^n))+(x^(m-1))+(x^m)+x)/(x+1)
simp all
