Back to Linear independence

Activity 2.4.3

Avg difficulty 2.5
  1. Explain why the homogeneous equation Ax=0A\xvec = \zerovec is consistent no matter the matrix AA.

  2. Consider the matrix A=[320−10−2211]A = \left[\begin{array}{rrr} 3 & 2 & 0 \\ -1 & 0 & -2 \\ 2 & 1 & 1 \end{array}\right] whose columns we denote by v1\vvec_1, v2\vvec_2, and v3\vvec_3. Describe the solution space of the homogeneous equation Ax=0A\xvec = \zerovec using a parametric description, if appropriate.

  3. Find a nonzero solution to the homogeneous equation and use it to find weights c1c_1, c2c_2, and c3c_3 such that c1v1+c2v2+c3v3=0c_1\vvec_1 + c_2\vvec_2 + c_3\vvec_3 = \zerovec.

  4. Use the equation you found in the previous part to write one of the vectors as a linear combination of the others.

  5. Are the vectors v1\vvec_1, v2\vvec_2, and v3\vvec_3 linearly dependent or independent?

Austin, Understanding Linear Algebra, §2.4 Linear independence, Activity 2.4.3

AI Tutor

Adapted from Understanding Linear Algebra © 2023 David Austin. Licensed under CC BY 4.0. Source: Understanding Linear Algebra. Imported at revision 3e6dced.