Find a particular solution ( yₚ ) of the following equation using the method of undetermined coefficients: ( y'' - 2y' + y = eˣ ).
a) ( yₚ = eˣ )
b) ( yₚ = xeˣ )
c) ( yₚ = eˣ + xeˣ )
d) ( yₚ = eˣ - xeˣ )