Solving high school functions with mathematical problems
(1) find f(0), f(0+b)=f(0)+f(b)+ 1 and get f (0) =- 1, f (x-x) = f (x)+f (-).
(2) Let x 1
(3) There is something wrong with the topic, which contradicts the conditions of the topic. If you have to do it, you can only do it, f6=f3+f3+ 1, f3=2, and because F is a decreasing function, M 2-3m- 1