### Overview

Linear approximation is a powerful application of a simple idea. Very small sections of a smooth curve are nearly straight; up close, a curve is very similar to its tangent line. We calculate linear approximations (i.e. equations of tangent lines) near x=0 for some popular functions; we can then change variables to get approximations near x=a.

### Lecture Video and Notes

### Video Excerpts

Clip 1: Introduction to Linear Approximation

Clip 2: Linear Approximation to ln x at x=1

Clip 3: Linear Approximation and the Definition of the Derivative

Clip 4: Approximations at 0 for Sine, Cosine and Exponential Functions

### Worked Example

Comparing Linear Approximations and Calculator Computations