#dy/dx = (d[(3x-1)(-3x^2-4)^-3])/dx#
#dy/dx = (3x-1)*(d[(-3x^2-4)^-3])/dx + ((-3x^2-4)^-3 ) (d(3x-1))/dx #
# dy/dx = 3*(-3x^2-4)^-3 + (3x-1)*(d[(-3x^2-4)^-3])/dx #
# dy/dx = 3*(-3x^2-4)^-3 + (3x-1)# #[-3*((-3x^2-4)^-4)*(d(-3x^2-4))/dx] #
# dy/dx = 3*(-3x^2-4)^-3 +18x*(3x-1)*(-3x^2-4)^-4 #
# dy/dx = 3/(-3x^2-4)^3 +18x*(3x-1)/(-3x^2-4)^4 #
# dy/dx = [3*(-3x^2-4) +18x*(3x-1)]/(-3x^2-4)^4 #
# dy/dx = [-9x^2 + 12 +54x^2-18x]/(-3x^2-4)^4 #
# dy/dx = [45x^2 -18x + 12]/(-3x^2-4)^4 #
# dy/dx = 3*[15x^2 -6x + 4]/(-3x^2-4)^4 #