Questions
Let u and v be vectors in R3. Consider the following statements.T or F (1) |u ...

Let u and v be vectors in R3. Consider the following statements.T or F

(1) |u·v|  ≤  ||u|| + ||v||
(2) If  au + bv = cu + dv then  a  =  c  and  b  =  d.

(3) ||u + v||2  =  ||u||2 + ||v||2 + 2(u·v)

Let u, v, and w be vectors in R3. T or F.

(1) u·v − ||u||
(2) (u·v) × w
(3) || ( ||u|| projvu ) ||

In: Advanced Math

Let a < c < b, and let f be defined on [a,b]. Show that f...

Let a < c < b, and let f be defined on [a,b]. Show that f ∈ R[a,b] if and only if f ∈ R[a, c] and f ∈ R[c, b]. Moreover, Integral a,b f = integral a,c f + integral c,b f .

In: Advanced Math

A vector y  =  [R(t)  F(t)]T describes the populations of some rabbits R(t) and foxes F(t). The...

A vector y  =  [R(t)  F(t)]T describes the populations of some rabbits R(t) and foxes F(t). The populations obey the system of differential equations given by y′  =  Ay where

A  = 

[−2

15]
[−2 9 ]


The rabbit population begins at 6000. If we want the rabbit population to grow as a simple exponential of the form R(t)  =  R0e3t  with no other terms, how many foxes are needed at time t  =  0?
(Note that the eigenvalues of A are λ  = 3 and 4.)

In: Advanced Math

The weighted voting systems for the voters A, B, C, ... are given in the form...

The weighted voting systems for the voters A, B, C, ... are given in the form q: w1, w2, w3, w4, ..., wn . The weight of voter A is w1, the weight of voter B is w2, the weight of voter C is w3, and so on. Calculate, if possible, the Banzhaf power index for each voter. Round to the nearest hundredth. (If not possible, enter IMPOSSIBLE.) {82: 53, 36, 24, 18} BPI(A) = BPI(B) = BPI(C) = BPI(D) =

In: Advanced Math

Graph Theory: Let S be a set of three pairwise-nonadjacent edges in a 3-connected graph G....

Graph Theory: Let S be a set of three pairwise-nonadjacent edges in a 3-connected graph G. Show that there is a cycle in G containing all three edges of S unless S is an edge-cut of G

In: Advanced Math

Let En be the subspace of V (n, 2) consisting of all vectros of even weight....

Let En be the subspace of V (n, 2) consisting of all vectros of even weight.

(a) What are the parameters [n, k, d] of En.

(b) Write down a generator matrix for En in standard form

In: Advanced Math

Solve the differential equation using undetermined coefficients: y''-0.25y=3sin0.5t where y(0)=0 and y'(0)=0

Solve the differential equation using undetermined coefficients:

y''-0.25y=3sin0.5t where y(0)=0 and y'(0)=0

In: Advanced Math

Problem 4 | A modied man-in-the-middle attack on Diffie-Hellman Suppose Alice and Bob wish to generate...

Problem 4 | A modied man-in-the-middle attack on Diffie-Hellman
Suppose Alice and Bob wish to generate a shared cryptographic key using the Diffie-Hellman
protocol. As usual, they agree on a large prime p and a primitive root g of p. Suppose also that
p = mq + 1 where q is prime and m is very small (so p - 1 = mq has a large prime factor, as
is generally required). Since g and p are public, it is easy for anyone to deduce m and q; for
example by successively trial-dividing p-1 by m = 2,4, 6, ...and running a primality test such
as the Fermat test on the quotient q = (p - 1)/m until primality of q is established.
Suppose an active attacker Mallory intercepts ga (mod p) from Alice and gb (mod p) from Bob.
She sends (ga)q (mod p) to Bob and (gb)q (mod p) to Alice.


(a) Show that Alice and Bob compute the same shared key K under this attack.


(b) Show that there are m possible values for K; and that Mallory can compute them
all and hence easily guess the correct key K among them.


(c) What is the advantage of this variation of the man-in-the-middle attack over
the version we discussed in class? Recall that for the attack from class, Mallory simply
suppresses the messages ga (mod p) and gb (mod p) between Alice and Bob and replaces
them with her own number ge (mod p), which results in the shared key gae (mod p) between
Mallory and Alice and the shared key gbe (mod p) between Mallory and Bob.

PLEASE SHOW CLEAR & DETAILED STEPS OF THE SOLUTIONS . THE PROOF SHOULD BE FOR GENERAL CASE, NOT AN EXAMPLE OF AN INDIVIDUAL CASE

In: Advanced Math

Use the Laplace transform to solve the given initial value problem. y'' + 2y' + 10y...

Use the Laplace transform to solve the given initial value problem.

y'' + 2y' + 10y = 6cos2t - 4sin2t, y(0)=2, y'(0)= -2

In: Advanced Math

how much do wild mountain lions weigh? adult wild mountain lions captured and released for the...

how much do wild mountain lions weigh? adult wild mountain lions captured and released for the first time in the san Andres mountains gave the following weights 68 108 125 125 60 64

In: Advanced Math

For which real values of a do there exist solutions of the differential equation y'' +...

For which real values of a do there exist solutions of the differential equation

y'' + 2y' + ay = 0

which satisfy the conditions y(0) = y(π) = 0 but which are not identically zero? For each such a give an appropriate non-zero solution

In: Advanced Math

A. Find a particular solution to the nonhomogeneous differential equation y′′ + 4y′ + 5y =...

A. Find a particular solution to the nonhomogeneous differential equation y′′ + 4y′ + 5y = −15x + e-x

y =

B. Find a particular solution to

y′′ + 4y = 16sin(2t).

yp =

C. Find y as a function of x if

y′′′ − 10y′′ + 16y′ = 21ex,

y(0) = 15,  y′(0) = 28, y′′(0) = 17.
y(x) =

In: Advanced Math

Question1: Consider a QR faction M=QR, show that R= Transpose(Q)M You need to show that (1)M...

Question1: Consider a QR faction M=QR, show that R= Transpose(Q)M

You need to show that (1)M = QR where R := Transpose(Q)M and (2) that R is upper triangular.

To show (1) use the fact that QTranspose(Q) is the matrix for orthogonal projection onto the image of M. What happens to a column of M (which is a vector in the image of M) when you project it onto the image of M?

To show (2), think about the entries of R := Transpose(Q)M as dot products between the columns v_1,...,v_n of M and the rows u_1,...,u_n of Q^T. Entries of Transpose(Q)M vanish when these vectors are orthogonal. The vectors u_1,..., u_n are the othonomal basis for the image of M obtained from v_1,...,v_n via the Gram-Schmidt process. Why is it the case that u_i.v_j =0 if i>j?

In: Advanced Math

(c) [2] For which of the following functions are the level curves linear?   (I) f(x, y)...

(c) [2] For which of the following functions are the level curves linear?  

(I) f(x, y) = tan(x + y)

(II) g(x, y) = e^y/x (e to the power of y over x)

(III) h(x, y) = ln(xy)

(A) none (B) I only (E) I and II (F) I and III

(C) II only (G) II and III

(D) III only (H) all three

A partial table of values for a function f(x,y) is given below. Which of the following are positive?

(I) fy(4, 1)

(II) fx(4, 1) (III) fxx(4, 1)

x=3

x=4

x=5

x=6

y=0

2.3

2.2

2.0

1.7

y=1

2.4

2.5

2.7

3.0

y=2

2.5

2.7

2.9

3.2

y=3

2.6

3.0

3.0

3.3

In: Advanced Math

*Combinatorics* Prove bell number B(n)<n!

*Combinatorics*
Prove bell number B(n)<n!

In: Advanced Math