MTH 222 Lecture Notes - Lecture 3: Row Echelon Form, Augmented Matrix, Solution Set

30 views2 pages

skyferret769

7 Sep 2016

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Any linear system"s solution set has the form: { + + + + such that are real numbers} Def: a square matrix (nxn) is singular if (a|) has a unique solution. Example: is singular because has a unique solution. 1. 3. 1 gauss-jordan reduction (read left to right) x y - 2w = 2 x + y + 3z + w = 1. Y + z - w = 0. Simplified, we would say x=w+, y=w - , z= - , w=w+0. This means the solution set is: w given that w is a real number. Definition: we say that two matrices are row equivalent if it is possible to perform elementary row operations to turn one row into another. With these matrices, simple operations make these matrices identical. This means that the two matrices are row equivalent, or that they have an equivalence relation. Theorem: every matrix is row equivalent to a unique reduced row echelon form matrix.

Related Questions

1. Consider the augmented matrix: (linear algebra)

a) Convert the matrix to echelon form

b) Obtain the reduced echelon form from the previous step

c) write a solution set for the corresponding system of equations

I have the answer for the following question. But some of theanswers are not correct.

Please do the following question by yourself and check which arethe wrong answers,please post your answers and compare to it.

Let r in and u =(1 1 0), v = (1 4 1), w = (r2 1 r2), b = (3+2r 5+12r 2r). For which values r in is the set {u. v, w} linearly independent? For which values r in is the vector b a linear combination of u. v and w? For which of these values of r can b be written as a linear combination of u. v and w in more than one way? The set 3 of all column vectors of length three, with real entries, is a vector space. Is the subset B = {(x y z) in 3 | xy + yz = 0} a subspace of 3? Justify your answer. Show that the set of all twice differentiable functions f : satisfying the differential equation sin(x) f"(x) + x2f(x) = 0 is a vector space with respect to the usual operations of addition of functions and multiplication by scalars. Here, f" denotes the second derivative of f. Let S be the following subset of the vector space 3 of all real polynomials p of degree at most 3: S = {p in 3 | p(l) = 0, p'(l) = 0}, where p' is the derivative of p. Determine whether S is a subspace of 3. Determine whether the polynomial q(x) = x - 2x2 + x3 is an element of S. u = (1 1 0), v = (1 4 1), w = (r2 1 r2) if {u, v, w} is linearly independent set 1(4r2 - 1)-1(r2 - r2) ne 0 4r2 ne 1 r ne plusmn1/2 this set is linearly independent set for values of e ne plusmn1/2 - - - - - - - (3+2r 5+12r 2r) = a1 (1 1 0) + a2 (1 4 1) + a3 (r2 1 r2) this forms system of equations in a1, a2, a3 if 4r2 - 1 ne 0 then system has unique solution if 4r2 - 1 = 0 and -2 - 4r = 0 rArr r = -1/2, the system has more than one solution if 4r2 - 1 ne 0 b can be written as linear combination of u,v,w as uniquely if r = -1/2 then b can be written as linear combination of u,v,w more than one way - - - - - - - - - (1 1 -1) in B and (1 0 1) in B (1 1 -1) + (1 0 1) = (2 1 0) not in B since 2times1+1times0 ne 0 so addition of vector is failed, this set is not forms subspace consider the following differential equation (sinx)f"(x) + x2f (x) = 0 each solution is continuous function the set of all solutions is subset of space of set of all continuous functions n from R to R let f,g are two solutions (sinx)f"(x) + x2f (x) = 0 (sinx)g"(x)+x2g(x) = 0 ccheck whether af+bg is solution or not (sinx)f"(x) + x2f(x) = 0 rArr (sinx) af"(x) + x2?f (x) = 0 (sinx)g"(x) + x2g (x) = 0 rArr (sinx)bg" (x) + x2bg (x) = 0 (sinx)(af"(x)+bg"(x)) +x2 (af (x) + bg(x)) = 0 af+bg is also solution to differential equation the set of all solutions to differential equation forms subspace - - - - - - - - - - consider the following subset of P3 {p in P3/.p(l)=0, p'(l) = 0} let p, q in S rArr p(l)= 0, p'(l) = 0 and q(l) = 0, q'(l) = 0 (ap + bq) (l) = ap (l) +b q(l) = a (0) + b (0) = 0 (ap + bq)'(1) = ap'(l) +bq'(1) = a (0) + b(0) = 0 p, q in S rArr ap +bq in S then S is subspace q(x) = x - 2x2 + x3 q(1) = 1 - 2 + 1 = 0 q'(x)=1 - 4x + 3x2 q'(l) = 1 - 4 + 3 = 0 q is element of S

MTH 222 Lecture Notes - Lecture 3: Row Echelon Form, Augmented Matrix, Solution Set

Document Summary

Get access

Related Documents

MTH 222 Lecture Notes - Lecture 2: Gaussian Elimination, Euclidean Vector, Row And Column Vectors

BMEN 2401 Lecture Notes - Lecture 10: Row Echelon Form, Augmented Matrix, Coefficient Matrix

MAT223H1 Study Guide - Midterm Guide: Row Echelon Form, Augmented Matrix, Solution Set

Related Questions