f(x+h) - f(x) h	=	1 x+h - 1 x h
	=	x - (x+h) x(x+h)h	We subtracted the fractions in the numerator Note that dividing by h puts it in the denominator
	=	-h x(x+h)h
	=	-1 x(x+h)	We canceled the "h"

Just close me to return to the tutorial.