(5) (10") Recall that for a unit vector ū in R, the matrix P = ūū...
(10) Recall that for a unit vector ū= in R2, the matrix P = ūūt represents the projection on ū. (a) Are there values a and b such that P is a SPD matrix? Explain. (b) Orthogonally diagonalize P. (c) Orthogonally diagonalize the reflection matrix L = 2P - I. (10) Determine the range of a so that the quadratic form Q(2, y, z) = a(z?+y2 +22)+2xy-2yz+2zz is positive definite.
Find a unit vector in the direction ū if ū is the vector from P(2,1, -3) to ((-1,0,4). Then, find c such that vector PR is orthogonal to ū where Ręc, c,c).
Exercise 1. Let v = 2 ER3. Recall that the transposed vector u is ū written in row form, 3 that is, of = [1 2 3]. It can be seen as a 1 x 3 matrix. For every vector R3, set f(w) = 1 WER. (i) Show that f: R3 → R defines a linear transformation. (ii) Show that f(ū) > 0. (iii) What are the vectors we R3 such that f(w) = 0?
5. Recall that a symmetric matrix A is positive definite (SPD for short) if and only if T Ar > O for every nonzero vector 2. 5a. Find a 2-by-2 matrix A that (1) is symmetric, (2) is not singular, and (3) has all its elements greater than zero, but (1) is not SPD. Show a nonzero vector such that zAx < 0. 5b. Let B be a nonsingular matrix, of any size, not necessarily symmetric. Prove that the matrix...
11. (8 marks) Given the vector ū = (3,-2, -5) (a) Find the unit vector with direction opposite to ū (b) Find the vector component of ū orthogonal to ū = (-1,2, -3)
Problem 13. Let l be the line in R' spanned by the vector u = 3 and let P:R -R be the projection onto line l. We have seen that projection onto a line is a linear transformation (also see page 218 example 3.59). a). Find the standard matrix representation of P by finding the images of the standard basis vectors e, e, and e, under the transformation P. b). Find the standard matrix representation of P by the second...
(a) Suppose that ū,ū e R". Show u2u-22||2 2해2 (b) (The Pythagoras Theorem) Suppose that u, v e R". Show that ul if and only if ||ü + 해2 (c) Let W be a subspace of R" with an orthogonal basis {w1, ..., w,} and let {ö1, ..., ūg} 22 orthogonal basis for W- (i) Explain why{w1, ..., üp, T1, .., T,} is an (ii Explain why the set in (i) spans R". (iii Show that dim(W) + dim(W1) be...
Only B Problem 5. Show that an element ū is a unit in R/PR, and find its inverse. (a) (15 pts) R=F3 [C], p= x4 + 2x +1, u = x2 +1. (b) (15 pts) R=Z[i], p= 8+ 7i, u = 1 – 2i.
Suppose that {ūj, ..., ūk} is an orthonormal basis for a subspace W of R" and we form the matrix U = (ū; ū2 ... ük) Then the matrix P= UUT has the property that p2 = P . This follows for the following reason(s). A. We know that P= I and so P2 = 1? = I = P B. We can calculate p2 = (UUT) (UUT) = U (UTU) UT = UIUT C. Since P is a projection...
(1 point) What is the matrix P-(P) for the projection of a vector b є R3 onto the subspace spanned by the vector a- ? 5 9 Pl 3 1 2 P21 23 - P32 31 What is the projection p of the vector b0onto this subspace? 9 Pl Check your answer for p against the formula for p on page 208 in Strang. (1 point) What is the matrix P-(P) for the projection of a vector b є R3...