558 CHAPTER 12 • FOURI ER SERIES AND THE LAPLACE TRANSFORM
y
y = j(t)
0 0
- I 2 3 4 5
- I
Figure 12.25
- Let f (t) be as gjven in Figure 12.26. Hint: The function is the integral of the one
in Exercise 13.
y
y =ft.ti
- I 2 3 4 5
Figure 12. 26
- Find c-• (1 -e -· -2•)
82- e.
For Exercises 17- 23, solve the initial value problem.
17. y" (t) + 2 y' (t) + 2y (t) = 0, with y (0) = - 1 and y' (0) = 1.
18. y" (t) + 4y' (t) + 5y (t) = 0, with y (0) = 1 and y' (0) = -2.
19. 2y" (t) + 2y' (t) + y (t) = 0, with y (0) = 0 and y' (0) = 1.
- y"(t)-2y'(t) +y(t) = 2e•, with y(O) = O and y' (0) = O.
- y" (t) + 2y' (t) + y (t) = 6te-•, with y (0) = 0 and y' (0) = O.
22. y" (t) + 2y' (t) + y (t) = 2U 1 (t) e•-•, with y (0) = 0 and y' (0) = 0.
- y" (t) + y (t) = Uw/2 (t), with y (0) = 0 and y' (0) = 1.