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Solve the given recurrence relation for the initial conditions given.

(a) an = 6an − 1 − 8an − 2; a0 = 1, a1 = 0
(b) an = 6an −1 − 9an − 2; a0 = 1, a1 = 1

1 Answer

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Final answer:

To solve the given recurrence relation, we use the characteristic equation method. For part (a), the general solution is an = A(4^n) + B(2^n), and for part (b), the general solution is an = (A + Bn)(3^n).

Step-by-step explanation:

To solve the given recurrence relation, we will use the characteristic equation method. For part (a), the characteristic equation is r^2 - 6r + 8 = 0. Factoring this equation, we get (r-4)(r-2) = 0, which gives us the roots r1=4 and r2=2. Therefore, the general solution to the recurrence relation is an = A(4^n) + B(2^n), where A and B are constants determined by the initial conditions. Substituting the initial conditions a0 = 1 and a1 = 0 into the general solution, we can solve for A and B.

For part (b), the characteristic equation is r^2 - 6r + 9 = 0, which factors to (r-3)^2 = 0. This gives us a repeated root r=3. The general solution is an = (A + Bn)(3^n), where A and B are again determined by the initial conditions. Substituting a0 = 1 and a1 = 1 into the general solution, we can solve for A and B.

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