Old Final Exam Solutions

1. y = Ae-cos x
2.  y = 3x + x-1/3
3. 

n

xn

yn

f(xn, yn)

yn+1 = yn + h·f(xn, yn)

Error

0 0 1       0           1 .2840
1 0.5 1     1         1.5 1.218281
2 1 1.5



4. Linearly Indepent
5. y(x) = A + Bx + Ce4x + Dxe4x
6. x(t) = 13 cos(6t - alpha),    alpha = arctan(-12/5) + 2Pi
7.  y(x) = (5/2)e-x - (8/3)e-2x + (1/6)ex
8. y(x) = (1/6)ex
9.  x(t) = -Ae-t + Be3t
     y(t) = A
e-t + Be3t
10. x(t) = -e-t + 4e3t
     y(t) = 
e-t + 4e3t

11.  r(t) = (-1/8) + (17/24)e4t+(5/12)e-2t
12.   F(s) = 6s/(s2+9)2
13.   y(t) = u(t-2)((-1/8) + (1/72)e8(t-2) + (1/9)e-(t-2))