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Evaluate lim(x to 2) (x^(3) - 3x^(2) + 4...

Evaluate `lim_(x to 2) (x^(3) - 3x^(2) + 4)/(x^(4) - 8x^(2) + 16)`

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To evaluate the limit \[ \lim_{x \to 2} \frac{x^3 - 3x^2 + 4}{x^4 - 8x^2 + 16}, \] we will follow these steps: ### Step 1: Substitute the value of \(x\) First, we substitute \(x = 2\) into the expression to check if we get a determinate form. \[ \text{Numerator: } 2^3 - 3(2^2) + 4 = 8 - 12 + 4 = 0, \] \[ \text{Denominator: } 2^4 - 8(2^2) + 16 = 16 - 32 + 16 = 0. \] Both the numerator and the denominator evaluate to 0, which gives us the indeterminate form \(\frac{0}{0}\). ### Step 2: Factor the numerator and denominator Since we have an indeterminate form, we need to factor both the numerator and the denominator. **Numerator:** The numerator \(x^3 - 3x^2 + 4\) can be factored or simplified. We can use polynomial long division or synthetic division to find the roots. Let's check if \(x = 2\) is a root: Using synthetic division with root \(2\): \[ \begin{array}{r|rrrr} 2 & 1 & -3 & 0 & 4 \\ & & 2 & -2 & -4 \\ \hline & 1 & -1 & -2 & 0 \\ \end{array} \] This gives us: \[ x^3 - 3x^2 + 4 = (x - 2)(x^2 - x - 2). \] Now, we can factor \(x^2 - x - 2\): \[ x^2 - x - 2 = (x - 2)(x + 1). \] Thus, the numerator becomes: \[ x^3 - 3x^2 + 4 = (x - 2)^2 (x + 1). \] **Denominator:** Now, we factor the denominator \(x^4 - 8x^2 + 16\). We can rewrite it as: \[ x^4 - 8x^2 + 16 = (x^2 - 4)^2 = (x - 2)^2 (x + 2)^2. \] ### Step 3: Rewrite the limit Now, we can rewrite the limit: \[ \lim_{x \to 2} \frac{(x - 2)^2 (x + 1)}{(x - 2)^2 (x + 2)^2}. \] ### Step 4: Cancel out the common factors We can cancel \((x - 2)^2\) from the numerator and denominator: \[ \lim_{x \to 2} \frac{x + 1}{(x + 2)^2}. \] ### Step 5: Substitute \(x = 2\) again Now we substitute \(x = 2\): \[ \frac{2 + 1}{(2 + 2)^2} = \frac{3}{4^2} = \frac{3}{16}. \] ### Conclusion Thus, the limit is: \[ \lim_{x \to 2} \frac{x^3 - 3x^2 + 4}{x^4 - 8x^2 + 16} = \frac{3}{16}. \]

To evaluate the limit \[ \lim_{x \to 2} \frac{x^3 - 3x^2 + 4}{x^4 - 8x^2 + 16}, \] we will follow these steps: ...
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