1. **Problem:** Evaluate the limit $$\lim_{x \to 2} f(x)$$ where $$f(x) = \frac{x^3 - 4x^2 + x + 6}{x^3 - 6x^2 + 11x - 6}$$.
2. **Formula and rules:** To find the limit of a rational function as $$x$$ approaches a value, first try direct substitution. If it results in an indeterminate form like $$\frac{0}{0}$$, factor numerator and denominator and simplify.
3. **Direct substitution:** Substitute $$x=2$$:
$$\text{Numerator} = 2^3 - 4(2)^2 + 2 + 6 = 8 - 16 + 2 + 6 = 0$$
$$\text{Denominator} = 2^3 - 6(2)^2 + 11(2) - 6 = 8 - 24 + 22 - 6 = 0$$
We get $$\frac{0}{0}$$, an indeterminate form.
4. **Factor numerator:**
$$x^3 - 4x^2 + x + 6$$
Group terms:
$$= (x^3 - 4x^2) + (x + 6) = x^2(x - 4) + 1(x + 6)$$
Try factoring by grouping or synthetic division. Testing $$x=2$$ as root:
$$2^3 - 4(2)^2 + 2 + 6 = 0$$ confirms $$x-2$$ is a factor.
Divide numerator by $$x-2$$:
Using synthetic division:
Coefficients: 1, -4, 1, 6
Bring down 1, multiply by 2: 2, add to -4: -2
Multiply by 2: -4, add to 1: -3
Multiply by 2: -6, add to 6: 0
Quotient: $$x^2 - 2x - 3$$
So numerator factors as:
$$ (x - 2)(x^2 - 2x - 3) $$
Further factor quadratic:
$$x^2 - 2x - 3 = (x - 3)(x + 1)$$
So numerator:
$$ (x - 2)(x - 3)(x + 1) $$
5. **Factor denominator:**
$$x^3 - 6x^2 + 11x - 6$$
Try $$x=2$$ as root:
$$2^3 - 6(2)^2 + 11(2) - 6 = 0$$ confirms $$x-2$$ is a factor.
Divide denominator by $$x-2$$:
Coefficients: 1, -6, 11, -6
Bring down 1, multiply by 2: 2, add to -6: -4
Multiply by 2: -8, add to 11: 3
Multiply by 2: 6, add to -6: 0
Quotient: $$x^2 - 4x + 3$$
Factor quadratic:
$$x^2 - 4x + 3 = (x - 3)(x - 1)$$
So denominator:
$$ (x - 2)(x - 3)(x - 1) $$
6. **Simplify:**
$$f(x) = \frac{(x - 2)(x - 3)(x + 1)}{(x - 2)(x - 3)(x - 1)}$$
Cancel common factors $$x - 2$$ and $$x - 3$$:
$$f(x) = \frac{x + 1}{x - 1}$$
7. **Evaluate limit:**
$$\lim_{x \to 2} f(x) = \lim_{x \to 2} \frac{x + 1}{x - 1} = \frac{2 + 1}{2 - 1} = \frac{3}{1} = 3$$
**Final answer:** $$\boxed{3}$$
Limit 5A 374896
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