Section D.1 Section 3.2
Exercises Exercises
1.
Check if the following functions are solutions to the given EQ.
- Check directly if y1=2e5t is a solution or not to y′′−6y′+5y=0.
- Check directly if y2=2et is a solution or not to y′′−6y′+5y=t.
2.
Recall that if y(t)=ert is a solution to the ODE given by
ay′′+by′+cy=0
for constant a,b,c where a≠0, then the exponent r in front the t must be a solution to the characteristic equation ar2+br+c=0.
By yourself, rederive that if y(t)=Aert is a solution to the equation above, then the number r must satisfy the characteristic equation ar2+br+c=0 or A=0.
3.
Use the method given in Section 3.2 to find the general solution to
y′′+5y′−6y=0
4.
Use the method given in Section 3.2 to find the general solution to
y′′−7y′=0
5.
Use the method given in Section 3.2 to find the particular solution to the IVP
y′′+y′−20y=0,y(0)=18,y′(0)=9