HP48/49 are able to find a solution y(T),
to a differential equation expressed as y'( T ) = f (T,y),
where the initial value of the function is given as y(to)=yo.
HP48/49 are able to solve differential equations in the numeric mode only.

Example:
Solve the Differential Equation
y' ( T ) = y + COS( T )
for y( 0 ) = 0 given that y( 0 ) = 0
1  write the Differential Equation in the field f 

2Access Solve Application:
Press: [NUM SLV] if you are using HP49.
[SOLVER] if you are using HP48.
and choose 2Solve dif eq.. 


3  write the Differential Equation in the field f 

4  enter independent
and dependent variables,
the limits and press [SOLVE]


Press [ENTER]
to see the result in the stack



What are the variables enclosed?

Variables enclosed are to, t and yo
Given a differential equation y'( T ) = y + COS( T ) to solve it
for y( T ) given that y ( to ) = yo the variables can be written
as in the picture beside.


Example
Solve the Differential Equation y'( T ) = y + COS( T )
for y( 3 ) given that y ( 1 ) = 2
Result:14.2307048559

