1. MAT 1235 Calculus II Section 9.5 Linear Equations http://myhome.spu.edu/lauw

2. HW and … WebAssign 9.5 (12 problems, 93 min.) Quiz 9.3 part I and 9.5 If 15 min. early tomorrow, then no class Friday

3. Linear (First Order) D.E. Technique: Multiply both side by the integrating factor

4. Example 1

5. 1. Verify is the general solutions 2. Q: Why not using ? A: Remarks

6. Example 2 **Reminder: Tell Wai to specify the interval at the end. He usually does not remember. You can take one point off from him. Ha, ha!

7. Remarks

8. Review: We learned… how to identify first order linear equations. how to compute and use the integrating factors to solve linear equations. we can ignore the integration constant in evaluating the integrating factors, with the understanding that the constant does not affect the solution. we need to “eliminate” the absolute value in the integrating factor (choose the biggest interval, or other methods*) not to interrupt the flow of the solutions by using the 2-column format.