Double Tower of Hanoi: In this variation of the Tower of Hanoi there are three poles in a row and 2n disks, two of each of n different sizes, where n is any positive integer. Initially one of the poles contains all the disks placed on top of each other in pairs of decreasing size. Disks are transferred one by one from one pole to another, but at no time may a larger disk be placed on top of a smaller disk. However, a disk may be placed on top of one of the same size. Let tn be the minimum number of moves needed to transfer a tower of 2n disks from one pole to another. a. Find q and t2.

b. Find t3.

c. Find a recurrence relation for t1, t2, t3,

a) t1 = 2 , t2 = 6

b) t3 = 14

c)  recurrence relation ( Tn ) = 2Tn-1 + 2

Step-by-step explanation:

Tn = minimum number of moves needed

2n disks is moved from one pole to another

a) determine the value of t1 and t2

let n = 1

2n moves = 2 * 1 = 2

∴ t1 = 2

let n = 2

2n moves = 2*2 = 4

∴ t2 = 4 + t1 = 4 + 2 = 6

b) determine value of t3

let n = 3

2n moves = 2 * 3 = 6

∴ t3 = t1 + t2 + 6

       = 2 + 6 + 6 = 14

c) Determine th recurrence relation

let n ≥ 2  i.e. n - 1 ≥ 1

number of disk required to be moved = 2n

number disks as follows : 1 to 2n

the recurrence relation = sum of number of moves in each step

                                    Tn = Tn-1 + 2 + Tn -1

hence recurrence relation ( Tn ) = 2Tn-1 + 2   when all integers n ≥ 2

c is the correct answer

step-by-step explanation:

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12