Session 5 Solution of First-Order Linear Equations 1. Mattuck video lecture 3 23:13 -- 42:50 Solve standard first order: integrating factor Example $xy' - y = x^3$ 2. Mattuck video lecture 3 42:50 -- 50:22 CC system $T' + kT = kT_e$ Definite integral soln to IVP 3. Doc 5.1 Integrating factors 4. Doc 5.2 radio quiz: intepret $k$. 5. Doc 5.3 radio quiz: Suppose x(t) measures temp in degrees C. What are the units on k? dx/dt? q_e? 6. Recitation video Orloff rec 1, topic 2, sugg prob 3. y'+2y=2 4. y'+2y=e^{2t} 7. y'+2y=2+5e^{2t} 8. Show y'+y^2=q does not satisfy superposition 7. Doc 5.4 Mattuck IR.4 discontinuous inputs use x'+kx=q 8. Haynes recit 4 problems ----------- Haynes lec 4 1. Homogeneous eq --> x_h 2. Diffusion eq (cc DE) example 3. Integrating factors 4. IC 5. General integrating factor (for non cc) -- Add in general solution x_p+cx_h -- Add in continuation theory from notes ch 3 Haynes notes ch3 Var of params Theory --continuation of solutions -------- Mattuck IR.1 y'+ky=q integrating factor IR.3 Temperature, physical inputs IR.4 Discontinuous inputs IR.5 Sinusoidal inputs