Log In Start studying!

Select your language

Suggested languages for you:
Answers without the blur. Sign up and see all textbooks for free! Illustration

Q16Q

Expert-verified
Linear Algebra and its Applications
Found in: Page 1
Linear Algebra and its Applications

Linear Algebra and its Applications

Book edition 5th
Author(s) David C. Lay, Steven R. Lay and Judi J. McDonald
Pages 483 pages
ISBN 978-03219822384

Answers without the blur.

Just sign up for free and you're in.

Illustration

Short Answer

Use Theorem 7 in section 1.7 to explain why the columns of the matrix A are linearly independent.

\(A = \left( {\begin{aligned}{*{20}{c}}1&0&0&0\\2&5&0&0\\3&6&8&0\\4&7&9&{10}\end{aligned}} \right)\)

The columns of matrix \(A\) are linearly independent according to theorem 7.

See the step by step solution

Step by Step Solution

Step 1: Denote the columns of matrix A

The columns of matrix \(A\) are denoted from right to left by vectors \({{\mathop{\rm v}\nolimits} _1},...,{{\mathop{\rm v}\nolimits} _4}\).

Step 2: Check if the columns of matrix A are linearly independent

Theorem 7 states that an indexed set \(S = \left\{ {{{\mathop{\rm v}\nolimits} _1},...,{v_p}} \right\}\) of two or more vectors is linearly dependent if and only if at least one of the vectors in \(S\) is a linear combination of the others. If \(S\) is linearly dependent and \({{\mathop{\rm v}\nolimits} _1} \ne 0\), then some \({{\mathop{\rm v}\nolimits} _j}\) is a linear combination of the preceding vectors \({{\mathop{\rm v}\nolimits} _1},...,{v_{j - 1}}\).

Vector \({{\mathop{\rm v}\nolimits} _1}\) is non-zero; \({{\mathop{\rm v}\nolimits} _2}\) is not a multiple of \({{\mathop{\rm v}\nolimits} _1}\) (since the third entry of \({{\mathop{\rm v}\nolimits} _2}\)is non-zero), and \({{\mathop{\rm v}\nolimits} _3}\) is not a linear combination of \({{\mathop{\rm v}\nolimits} _1}\) and \({{\mathop{\rm v}\nolimits} _2}\) (since the second entry of \({{\mathop{\rm v}\nolimits} _3}\) is non-zero). Furthermore, \({{\mathop{\rm v}\nolimits} _4}\) cannot be a linear combination of \({{\mathop{\rm v}\nolimits} _1},{{\mathop{\rm v}\nolimits} _2},\) and \({{\mathop{\rm v}\nolimits} _3}\), based on the first entry in the vector. Thus, the columns are linearly independent according to theorem 7.

Recommended explanations on Math Textbooks

94% of StudySmarter users get better grades.

Sign up for free
94% of StudySmarter users get better grades.