SOLVING DIFFERENTIAL EQUATIONS ON TI 89 TITANIUM.
To solve type I differential equation
dy
= x 2 + e 2 x you need to re-write it in
dx
the following form: y′ = x 2 + e 2 x
Then select F3, deSolve( y′ = x 2 + e 2 x ,x,y)
Clear a-z before you start at any new DE.
The answer is given with the constant ϑ1
as it is a general solution.
To find the particular solution to the
following DE:
dx
= 2t 3 − 3, x(0) = 3 , type
dt
deSolve( x′ = 2t 3 − 3 and x(0) = 3, t , x)
Sometimes the general solution to a DE
can be given implicitly as in the
following example:
dy
y
= 2 x2
dx
To make y the subject solve for y.
Try the following DE:
dy
1
=
, y (0.5) = 0
dx
1 − 2 x2
To solve the second order differential equation such
as:
d2y
a.
+ y =3
dx 2
d 2 y dy
b.
+
= 1 type as shown on the right:
General solutions are obtained
dx 2 dx
above.
©Bozenna Graham 2009
Bozenna.Graham@wesleycollege.net 1
To find the particular solution to the following
second order DE:
d 2 y dy
dy
+
= 1,
= 3 and y = 1 when x = 0.
2
dx
dx
dx
Type:
deSolve( y′′ + y′ = 1 and y (0) = 1 and y′(0) = 3, x, y )
The particular solution is
obtained now.
©Bozenna Graham 2009
Bozenna.Graham@wesleycollege.net 2