72.13 Chapter 3. Second order linear equations. Section 18. The Method of Undetermined Coefficients. Problems at page 132

72.13.1 problem 1 (a)
72.13.2 problem 1 (b)
72.13.3 problem 1 (c)
72.13.4 problem 1 (d)
72.13.5 problem 1 (e)
72.13.6 problem 1 (f)
72.13.7 problem 1 (g)
72.13.8 problem 1 (h)
72.13.9 problem 1 (i)
72.13.10 problem 1 (j)
72.13.11 problem 1 (k)
72.13.12 problem 2
72.13.13 problem 3 (a)
72.13.14 problem 3 (b)