Problems On Method Of Undetermined Coefficients

Problems on Method of Undetermined Coefficients:

3. Solve using the method of undetermined method:

y'' - 5y' 6y = sin 2x.

Solution: we have (D2 - 5D 6)y = sin 2x

             A.E is m2 - 5m 6 = 0

            (m-2) (m-3) = 0

            ∴ m = 2,3


We assume for the P.I in the form


We have to find 'a' and 'b' such that





Comparing the coefficient we get:


Solving we get;


From the above equations:


4. Solve by the method of undetermined coefficient:

   y'' y' - 2y = x sinx

Solution: We can solve this equation with the help of above metod.