
10.4. Construct the phase diagram for the equation ¨x − ω
2
n
x = 0.
Solution: We rewrite the equation as
˙x (t) = y (t)
˙y (t) = ω
2
n
x (t) ,
The figure below shows the phase diagram. The Matlab code given in Problem 10.3 can be re used with the
function F modified. We can also use quiver.m.
Solution to Problem 10.4. ω
n
is set to 1.
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