**Learning objectives**

- Find coordinates relative to an orthonormal basis
- Use an orthonormal basis to compute projections onto a subspace
- Understand orthogonal transformations geometrically

**Before class**

- Read Lay sections 6.2 and 6.3
- Consult notes to the textbook (if you wish)
- Ponder Lay problems 6.2: 27; 6.3: 1, 3, 11, 21.
- Post to Piazza
- Work on webwork problems
- Write solutions to problems 5.4: 6, 8 and 6.1:20, 28 to turn in at the beginning of class.

**In class**