Explanation:
those are the x values in the graph above
now the slope
first, find the derivative = (-2*x)/(9+(6*x^2)+x^4)+(50*Cos(x))/(3+x^2)+((-100*x)*Sin(x))/(9+(6*x^2)+x^4)
then substitute the X values
the slope at first point=0.00214262528
the slope at secondpoint=0.29521512101
the slope at the third point=0.29521512101