We had, from the last question

f(x+h) - f(x) h

=

-1 x(x+h)

Taking the limit as h 0 gives

f'(x)	=	lim h0	f(x+h) - f(x) h	=	lim h0	-1 x(x+h)
				=	-1 x2		We just put h = 0 at this stage

Enter this as -1/x^2

Just close me to return to the tutorial.