MCQ Bank
The set of least-square solutions of $Ax=b$ coincides with the nonempty set of solutions of the normal equation
- A) None of these
- B) $A^{T} A \widehat x =A^{T}b$
- C) $A^{T} A\widehat x =A^{T}$
- D) $A\widehat x=A^{T}$
Orthonormal set is a set of all vectors that are
- A) Mutually orthonormal and are of unit length
- B) Mutually orthonormal and of null length
- C)
- D)
The set of least square solutions of Ax=b coincides with the non-empty set of solutions of the normal equations
- A) ${A^T}\mathop x\limits^{-} A = b{A^T}$
- B) ${A^T}\mathop x\limits^{-} A = b{A^T}$
- C)
- D)
Let $$s = \{ {u_1} + {u_2} + ......{u_p}\}$$ be a basis for a subspace W of $${R^n}$$ , is also an orthogonal basis if S is an orthogonal set.
- A) False
- B) True
- C)
- D)
A square matrix with _______ columns is an orthogonal matrix.
- A) orthonormal
- B) even
- C) orthogonal
- D) same
If a _____ matrix has orthonormal columns, then it also has orthonormal rows.
- A) singular
- B) square
- C) rectangular
- D) diagonal
Let B and C denote subsets of a vector space V.
- A) If B $$\subseteq$$C then span(C) = span(B).
- B) If B $$\subseteq$$C and C is dependent, then B is dependent.
- C) If B$$\subseteq$$ C and C spans V then B spans V.
- D) If B $$\subseteq$$C and C is independent then B is independent.
Two vectors are _______if at least one of the vector is a multiple of the other
- A) linearly dependent
- B) linearly independent
- C)
- D)
The matrix ${A^T}A$ is invertible If and only if the columns of A are ------
- A) Linearly dependent
- B) None of the above
- C) Equal
- D) linearly independent
Let be a five-dimensional vector space, and let be a subset of consisting of five vectors. Then S
- A) Must be linearly independent, but cannot span V
- B) Must be linearly dependent, but may or may not span V
- C)
- D)
The matrix $A^{T}A$ is invertible iff the columns of A are-----------------------
- A) Linearly dependent
- B) Linearly independent
- C)
- D)
Any finite dimensional inner product space possesses an orthonormal basis
- A) True
- B) False
- C)
- D)
For u and v vectors in $R^n$, thw distance between u and v written as $dist(u, v)$ is the length of the vector------
- A) $v-u$
- B) $u-v$
- C)
- D)
If A is an m x n matrix with linearly independent columns, then A can be factored as A = QR, where Q is an m x n matrix whose columns form an orthonormal basis for Col A and R is an n x n upper triangular invertible matrix with positive entries on its diagonal
- A) True
- B) False
- C)
- D)
Let $W$ is a finite dimensional subspace of an inner product space $V$ and $y$ is any vector in $V$. The best approximation to $y$ from $W$ is then
- A) $Proj^{y}_{w}$
- B) $Proj^{w}_{y}$
- C)
- D)
The two vectors are said to be equivalent if:
- A) None of the above
- B) Both (a) and (b).
- C) Same length.
- D) Same direction
The matrix A^T(Transpose of A) x A is invertible if and only if the columns of A are _________.
- A) linearly dependent
- B) linearly independent
- C)
- D)
The matrix [Math Processing Error]ATA${A^T}A$ is invertible If and only if the columns of A are ------
- A) None of the above
- B) linearly independent
- C) Linearly dependent
- D) Equal
A m ×n matrix U has orthonormal columns if and only if [Math Processing Error]$${U^t}U = I$$
- A) False
- B) True
- C)
- D)
The only 0-dimensional subspace of {R^3} is
- A) Infinite space
- B) \left\{ {a,b} \right\}
- C) None of the above
- D) Zero space