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Let $$f(x) = x^3 + x^2 f'(1) + x f''(2) + f'''(3), \; x \in \mathbb{R}$$. Then $$f'(10)$$ is equal to _______.
Correct Answer: 202
Let $$f(x) = x^3 + x^2 f'(1) + x f''(2) + f'''(3)$$.
Let $$f'(1) = a$$, $$f''(2) = b$$, $$f'''(3) = c$$.
$$f(x) = x^3 + ax^2 + bx + c$$
$$f'(x) = 3x^2 + 2ax + b$$
$$f''(x) = 6x + 2a$$
$$f'''(x) = 6$$
From $$f'''(3) = c$$: $$c = 6$$.
From $$f''(2) = b$$: $$12 + 2a = b$$.
From $$f'(1) = a$$: $$3 + 2a + b = a$$, so $$b = -a - 3$$.
From the two equations for b:
$$12 + 2a = -a - 3$$
$$3a = -15$$
$$a = -5$$
$$b = -(-5) - 3 = 2$$
$$f'(x) = 3x^2 - 10x + 2$$
$$f'(10) = 300 - 100 + 2 = 202$$
The answer is $$\boxed{202}$$.
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