Tangent line to $$$y = x^{3} - 3 x + 2$$$ at $$$x = 2$$$
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Calculate the tangent line to $$$y = x^{3} - 3 x + 2$$$ at $$$x = 2$$$.
Solution
We are given that $$$f{\left(x \right)} = x^{3} - 3 x + 2$$$ and $$$x_{0} = 2$$$.
Find the value of the function at the given point: $$$y_{0} = f{\left(2 \right)} = 4$$$.
The slope of the tangent line at $$$x = x_{0}$$$ is the derivative of the function, evaluated at $$$x = x_{0}$$$: $$$M{\left(x_{0} \right)} = f^{\prime }\left(x_{0}\right)$$$.
Find the derivative: $$$f^{\prime }\left(x\right) = \left(x^{3} - 3 x + 2\right)^{\prime } = 3 x^{2} - 3$$$ (for steps, see derivative calculator).
Hence, $$$M{\left(x_{0} \right)} = f^{\prime }\left(x_{0}\right) = 3 x_{0}^{2} - 3$$$.
Next, find the slope at the given point.
$$$m = M{\left(2 \right)} = 9$$$
Finally, the equation of the tangent line is $$$y - y_{0} = m \left(x - x_{0}\right)$$$.
Plugging the found values, we get that $$$y - 4 = 9 \left(x - 2\right)$$$.
Or, more simply: $$$y = 9 x - 14$$$.
Answer
The equation of the tangent line is $$$y = 9 x - 14$$$A.