Calculate the derivative at a point using the definition of limit
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2) $f(x) = 4x^3 + 5x^2 - 10x + 4$
$\lim_{x \to 2} \frac{f(x) - f(2)}{x - 2} = f'(2)$
$12x^2 + 10x - 10 + 0 = f'(x)$
$48 + 20 - 10 = 58$
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Hi Bildanur, let's solve this calculus problem together. We are asked to evaluate the limit of f of x minus f of two over x minus two, as x approaches two.
Calculating the Limit
First, let's recognize that this limit expression is actually the definition of the derivative of the function at the point where x equals two.
So, instead of computing the limit directly, we can find the derivative f prime of x and then substitute two into it.
Let's perform the differentiation. We use the power rule, which says that the derivative of x to the power of n is n times x to the power of n minus one.
Step 1: Find $f'(x)$
For the first term, four x cubed, the derivative is four times three, which is twelve, times x squared.
Next, the derivative of five x squared is five times two, which is ten, times x.
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