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Linear Algebra

Sum of two random variables

Z=sum of dots (uniform on {1,2,3,4,5,6} a. M_z(s)=? b. M_z(s)=M_x(s)^2 why? M_z stands for the mgf of x=sum of dots when two dice are tossed


Once you obtain eigenvalues of 8.248, 7.661, and -3.909 for the matrix 1 5 -3 5 4 2 -3 2 7 what are the next steps to obtain the eigenvectors.

Linear Algebra

Let A be a 4x4 matrix with minimal polynomial m(t)=(t^2 + 1)(t^2 - 3). Find the rational canonical form for A if A is a matrix over (a) the rational field Q (b)the real field R, (c) the complex field C.

Linear Algebra

Let T be a linear operator on a finite dimensional vector space V. Suppose the minimal polynomial for T is of the form P^n where p is an irreducible polynomial over the scalar field. Show that there is a vector x in V such that the T-annihilator of x is p^n.

Linear Algebra Question

1. Let V be a vector space of odd dimension (greater than 1) over the real field R. Show that any linear operator on V has a proper invariant subspace other than {0}.

Perturbed Linear System

Consider the perturbed linear system x' = (A + eB(t))x, x is an element of R^n, where A is a constant matrix, B is a bounded continuous matrix valued function, and e is a small parameter. Assume that all eigenvalues of A have non-zero real part. 1) Show that the only bounded solution of the system is 0. 2) If A ha

Systems of Equations : Applications to Perimeter of a Rectangle

Write as a system of 2 equations in 2 unknowns. Solve each system by substitution and show each step. Perimeter of a rectangle : the length of a rectangular swimming pool is 15 feet longer than the width. If the perimeter is 82 feet, what are the length and width?

Systems of Equations : Five Word Problems

There are hens + rabbits. The heads = 50 the feet = 134. How many hens & how many rabbits ? Flies + spiders sum 42 heads and 276 feet. How many of each class? J received $1000 and bought 9 packs of whole milk & skim milk that totalled $960 - How many packs bought of each kind? A number is composed of two integers and its sum


Solve the following cryptogram doing the following steps: 1. frequency count 2. do you think it is monoalphabetic substitution, polyalphabetic subsitution, or transposition? 3. Is this a clear decision? 4. Solve based on the above info. DVOLL PULID ZIWGL ZDLIO WULFM WVWFM WVWFK LMULF IVHHV MGRZO SFNZM UIVVW LNHGS VUR

Linear Algebra : Wronskian

Compute the Wronskian of the given set of functions, then determine whether the function is linearly dependent or linearly independent: x^2 - x, x^2 + x, x^2, all x

Linear algebra

Show that the set of all elements of R^3 of the form (a + b, -a, 2b), where a and b are any real numbers, is a subspace of R^3. Show that the geometric interpretation of this subspace is a plane and find its equation.

Subgoups : Indicies

Note: C means set containment (not proper set containment), |G : K| means index of subgroup K in G, and G # K means K is a normal subgroup of G question: Let K C H C G be groups, where K # G and |G : K| is finite. Show that |G/K : H/K| is also finite and that |G/K : H/K|=|G : H|

Finding eigenvalues

Let Tn = (tij) denote the nxn matrix such that for each index i, tji = a and tij = b for j not = to i. Verify that Tn = (a-b)In + bEn where En is the nxn matrix of all 1's. Find the determinate and the eigenvalues of Tn.