Your input: find the difference quotient for f(s)=s−12s2.
A difference quotient is given by f(s+h)−f(s)h
To find f(s+h), plug s+h instead of s:
f(s+h)=s−12s2
Finally, f(s+h)−f(s)h=(s−12s2)−(s−12s2)h=0
Answer: the difference quotient for f(s)=s−12s2 is 0.