\[f(x) = \frac{1}{4}x^{2} - x\]
\[f( - 2) = \frac{1}{4} \cdot 4 + 4 = 1 + 4 = 5.\]
\[f(3) = \frac{1}{4} \cdot 9 - 3 = \frac{9}{4} - 3 =\]
\[= 2,25 - 3 = - 0,75.\]