3. Найти f (5), f(-2), f(0), если f(x) = x²-12x.

Для функции $$f(x) = x^2 - 12x$$: $$f(5) = 5^2 - 12 \cdot 5 = 25 - 60 = -35$$ $$f(-2) = (-2)^2 - 12 \cdot (-2) = 4 + 24 = 28$$ $$f(0) = 0^2 - 12 \cdot 0 = 0 - 0 = 0$$ Ответ: $$f(5) = -35$$, $$f(-2) = 28$$, $$f(0) = 0$$