- #1
doroulla
- 16
- 0
hi. I can't figure out this question:
d2y/dx2 - 2 dy/dx - 3y = x
(i) find complementary function
(ii) find particular integral
(iii) using (i) and (ii) find the general solution
(iv) find the solution that satisfies the initial conditions:
y=2/9 at x=0 and dy/dx=-13/3 at x=0
i did:
m^2 - 2m - 3 = 0
(m-3)(m+1)=0
real and distinct solutions thus
y = Ae^(3x) + Be^(-x)
thus dy/dx = 3Ae^3x - Be^-x
d2y/dx2 = 9Ae^3x + Be^-x
now i have no idea how to continue. As i understood what i found above is the complementary function. I think. Thank you
d2y/dx2 - 2 dy/dx - 3y = x
(i) find complementary function
(ii) find particular integral
(iii) using (i) and (ii) find the general solution
(iv) find the solution that satisfies the initial conditions:
y=2/9 at x=0 and dy/dx=-13/3 at x=0
i did:
m^2 - 2m - 3 = 0
(m-3)(m+1)=0
real and distinct solutions thus
y = Ae^(3x) + Be^(-x)
thus dy/dx = 3Ae^3x - Be^-x
d2y/dx2 = 9Ae^3x + Be^-x
now i have no idea how to continue. As i understood what i found above is the complementary function. I think. Thank you