Consider the quadratic form Q(x) xỈ + x2 + x + 4X1X2 + 4x2x3 + 4x3x1. (a) Find the real symmetric...
5.3.15 Consider the quadratic form tx In (5.3.21) 1) Find a symmetric matrix A E R(n, n) such that q(x)-x' Ax for (ii) Compute the eigenvalues of A to determine whether q or A is pos- r E R" itive definite,
Quadratic forms arise often in geometry, physics and engineering and it is desirable to reduce these to canonical (standard) forms. Reduce the quadratic form:Q = 3x12 + 5 x22 + 3x32 - 2x2 x3 + 2x1 x3 - 2 x1 x2 to a standard form by making an approximate change in variables X = MY , where M is an orthogonal matrix. i) Write Q as X T AX . ii) Find the Eigenvalues of A. Is the quadratic form...
Let Q(x)- 355x35x3 -40x,*2 20x,X3+40x2X3 Find a unit vector x in R3 at which Q(x) is maximized, subject to x x-1. [Hint: The eigenvalues of the matrix of the quadratic form Q are 45 and 15.] A unit vector that maximizes Q(x) is u Type an exact answer, using radicals as needed.)
1. (10 points) Consider quadratic form q ) = ? Aš where: 1 0 C A= -2 3 -2 T=Y -3 -4 -5 ܠܛ 2 (a) Find a symmetric matrix Q such that q(7) = 2 Q7. (b) Determine whether the quadratic form q is positive definite, positive semidefinite, negative definite, negative semidefinite, or indefinite.
Theorem. Consider the quadratic form Q(x) = Ar where A is anxn symmetric matrix and A, and denote the largest and smallest eigenvalues of A, respectively. Then max Q(x) = 2 = max Q() = 1 and Q0.) = 1, where is any unit eige vector corre sponding to ii) in (r) and QU.) where is any unit eigen vector corresponding to do 1. - Find max Q(x) and min Q(x). 1) Q(1) = 3x + 43273 +673 ii) Q(z)...
4. (a) Find the symmetric matrix A associated with the quadratic form, q = 5x - 4.1112+5x3, and compute the eigenvalues X, and 12 and the associated normalized eigenvectors e, and e2 of A. (b) Use the result of Part (a) to determine the spectral decomposition for A PAP. 22), and y. . wal. Rewrite q = (c) Let x = Py, where P is in Part (b), x = ( 5x - 4x32 +503 in y-variables, yı and y2.
Consider the quadratic form Q(1, 2, r)2r2r34rs. Write Q(, 2, 3) in the fornm Q(1, 2, z3)xAx for some matrix A to be found, where x-2 T3 Classify Q(x1, r2, r3) as positive definite, negative definite, positive semidefinite, negative semidefinite, or indefinite
Exercise 2 Consider the symmetric matrix A a13 23 012 a13 023 , the quadratic form .q(z) = z'Az, associated T2 T3 1. Show that for x = with the symmetric matrix A is 2. Using the result from question (1), find the matrix associated with the quadratic forms below. Assumed that x is in IR3
5. (a) State the Spectral Theorem for Symmetric matrices. (b) Write out the spectral factorization of =(22 (c) Using the change of variables x Qy, where Q is an appropriate orthogonal matric, express the quadratic form 5ri + 4r1t2 2 in terms of yi and y2. Describe and sketch the graph of the equation 5xi +4z1t2 +22 1 in the z1, z2 plane (d) Find the spectral decomposition of A. 5. (a) State the Spectral Theorem for Symmetric matrices. (b)...
Find an orthogonal change of variables that eliminates the cross product terms in the quadratic form Q, and express Q in terms of the new variables. 7x{ + 6x2 + 5x3 - 4X1X2 + 4x2X3 A substitution x = Py that eliminates cross-product terms is X1 = o A substitution x = Py that eliminates cross-product terms is Xi = – -}y.+3y2– žys, x2 = - - Žy2+3y2 +3v3, x3 = - {yı+ {y2– žv3. The new quadratic form is...