Solve the nonhomogeneous recurrence relation hn4hn1 4hn23n 1
Solve the nonhomogeneous recurrence relation hn=4h(n-1) -4h(n-2)+3n +1, h0=1, h1=2
Solution
First we solve the homogeneous recurrence assoaciated with problem
hn=4h(n-1)-4h(n-2)
It is linear homogneous with constant coefficients so we look for hn=r^n
Substituting gives
r^2-4r+4=0
r=2, repeated root
SO general solution is
hn=2^n(A+Bn)
For the inhomogneous we guess a particular solution based on inhomogenous part ie 3n+1
LEt, An+B be the guess
Substituting gives
An+B=4A(n-1)+4B-4A(n-2)-4B+3n+1
An+B=4A+3n+1
Hence, A=3, B=4A+1=13
hn=3n+13
hn=2^n(A+Bn)+3n+13
h0=A+13=1
A=-12
hn=2^n(-12+Bn)+3n+13
h1=2(-12+B)+16=2
2(-12+B)=-14
-12+B=-7
B=5
hn=2^n(-12+5n)+3n+13
