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ind the equation of the tangent line to the graph of the given function at the point with the indicated x-coordinate. f(x) = x3; x = −2

User RodriKing
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1 Answer

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Final answer:

To find the equation of the tangent line at x = -2 for the function
f(x) = x^3, calculate the derivative, evaluate it at x = -2 to get the slope, and use the point-slope form with the point (-2, -8) to obtain the equation y = 12x + 16.

Step-by-step explanation:

To find the equation of the tangent line to the graph of the function
f(x) = x^3 at the point with the x-coordinate x = -2, you need to follow these steps:

  1. Calculate the derivative of f(x) to find the slope of the tangent line at any point.
  2. Find the slope at x = -2 by plugging it into the derivative.
  3. Use the point-slope form of the equation for a straight line to write the equation of the tangent line.

Let's go through the steps:

  1. The derivative of
    f(x) = x^3 is
    f'(x) = 3x^2.
  2. Substituting x = -2 into f'(x) gives the slope:
    f'(-2) = 3(-2)^2 = 12.
  3. The point on the curve is
    (-2, (-2)^3) or (-2, -8). Now we use the point-slope form: y - y1 = m(x - x1), which gives us y + 8 = 12(x + 2).

Therefore, the equation of the tangent line is y = 12x + 16.

User Der Kommissar
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