Solution From the graph of the given function
(Fig 6 9) , note that
f (x) ≥ 0, for all x ∈ R and  f (x) = 0  if  x = 0 Therefore, the function f has a minimum value 0
and the point of minimum value of f is x = 0 Also, the
graph clearly shows that f has no maximum value in R
and hence no point of maximum value in R