After completing this section, students should be able to do the following.

  • Define linear approximation as an application of the tangent to a curve.
  • Find the linear approximation to a function at a point and use it to approximate the function value.
  • Identify when a linear approximation can be used.
  • Label a graph with the appropriate quantities used in linear approximation.
  • Find the error of a linear approximation.
  • Compute differentials.
  • Use the second derivative to discuss whether the linear approximation over or underestimates the actual function value.
  • Contrast the notation and meaning of versus .
  • Understand that the error shrinks faster than the displacement in the input.
  • Justify the chain rule via the composition of linear approximations.