Corresponding homogeneous differential equation
y′′−3y′+2y=0 Characteristic (auxiliary) equation
r2−3r+2=0
r1=1,r2=2 Find a particular solution in form yp=x(Ax+B)ex+C.
yp=Ax2ex+Bxex+C
yp′=Ax2ex+2Axex+Bxex+Bex
yp′′=Ax2ex+4Axex+2Aex+Bxex+2Bex
Ax2ex+4Axex+2Aex+Bxex+2Bex
−3Ax2ex−6Axex−3Bxex−3Bex
+2Ax2ex+2Bxex+2C=xex+1
−2A=1
2A−B=0
2C=1
A=−1/2,B=−1,C=1/2 The particular solution is
yp=−21x2ex−xex+21
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