kill(all)$

van=facebook.com/LearningCalculus$

f(a,b,c):=a*(1-b)+b*(1-c)+c*(1-a);

delta:1;

for a:0 thru 1 step (delta) do
for b:0 thru 1 step (delta) do
for c:0 thru 1 step (delta) do
(
    ff:f(a,b,c),
    if (0 <= ff) and (ff <= 1) then (print("answer a: ", a," b: ", b," c: ", c," f: ", ff))
);