Solve these recurrence relations together with the initial conditions given. a) an= an−1+6an−2 for n ≥ 2, a0= 3, a1= 6 b) an= 7an−1−10an−2for n ≥ 2, a0= 2, a1= 1 c) an= 6an−1−8an−2for n ≥ 2, a0= 4, a1= 10 d) an= 2an−1−an−2for n ≥ 2, a0= 4, a1= 1 e) an= an−2for n ≥ 2, a0= 5, a1= -1 f) an=− 6an−1−9an−2for n ≥ 2, a0= 3, a1= -3 g) an+2 = -4an+15anfor n ≥ 0, a0= 2, a1= 8

Step-by-step explanation:

These homogeneous recurrence relations of degree 2 have one of two solutions. Problems a, b, c, e, g have one solution; problems d and f have a slightly different solution. The solution method is similar, up to a point.

If there is a solution of the form , then it will satisfy ...

Rearranging and dividing by , we get the quadratic ...

The quadratic formula tells us values of r that satisfy this are ...

We can call these values of r by the names r₁ and r₂.

Then, for some coefficients p and q, the solution to the recurrence relation is ...

We can find p and q by solving the initial condition equations:

These have the solution ...

_____

Using these formulas on the first recurrence relation, we get ...

a)

__

The rest of (b), (c), (e), (g) are solved in exactly the same way. A spreadsheet or graphing calculator can ease the process of finding the roots and coefficients for the given recurrence constants. (It's a matter of plugging in the numbers and doing the arithmetic.)

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For problems (d) and (f), the quadratic has one root with multiplicity 2. So, the formulas for p and q don't work and we must do something different. The generic solution in this case is ...

The initial condition equations are now ...

and the solutions for p and q are ...

__

Using these formulas on problem (d), we get ...

d)

__

And for problem (f), we get ...

f)

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Comment on problem g

Yes, the bases of the exponential terms are conjugate irrational numbers. When the terms are evaluated, they do resolve to rational numbers.

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step-by-step explanation:

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answer: solve 5\cdot 2^x=2405⋅2  

x

=2405, dot, 2, start superscript, x, end superscript, equals, 240.

solution

to solve for xxx, we must first isolate the exponential part. to do this, divide both sides by 555 as shown below. we do not multiply the 555 and the 222 as this goes against the order of operations!

\begin{aligned} 5\cdot 2^x& =240 2^x& =48 \\ \end{aligned}  

5⋅2  

x

2  

x

​    

=240

=48

​

step-by-step explanation: