Lời giải:
a)
\(f(0)=\frac{-0}{2}+3=3\)
$f(1)=\frac{-1}{2}+3=\frac{5}{2}$
$f(-1)=\frac{-(-1)}{2}+3=\frac{7}{2}$
$f(2)=\frac{-2}{2}+3=2$
$f(6)=\frac{-6}{2}+3=0$
$f(\frac{1}{2})=\frac{-\frac{1}{2}}{2}+3=\frac{11}{4}$
b)
\(f(x)=2x-3\Rightarrow f(x+1)=2(x+1)-3=2x-1\)
Do đó: \(f(x+1)-f(x)=2x-1-(2x-3)=2\)
c)
\(f(2)=3.2-9=-3\)
\(f(-2)=3(-2)-9=-15\)
\(g(0)=3-2.0=3\)
\(g(3)=3-2.3=-3\)