Mark each statement True or False. Justify each answer.
a. A homogeneous equation is always consistent.
A. True. A homogenous equation can be written in the form [tex]A x=0[/tex], where [tex]A[/tex] is an [tex]m \times n[/tex] matrix and 0 is the zero vector in [tex]R^m[/tex]. Such a system [tex]A x=0[/tex] always has at least one nontrivial solution. Thus a homogenous equation is always consistent.
B. False. A homogenous equation can be written in the form [tex]\mathrm{Ax}=\mathbf{0}[/tex], where [tex]\mathrm{A}[/tex] is an [tex]\mathrm{m} \times \mathrm{n}[/tex] matrix and [tex]\mathbf{0}[/tex] is the zero vector in [tex]\mathbb{R}^m[/tex]. Such a system [tex]\mathrm{Ax}=\mathbf{0}[/tex] always has at least one solution, namely, [tex]\mathbf{x}=0[/tex]. Thus a homogenous equation is always inconsistent.
C. True. A homogenous equation can be written in the form [tex]A \mathbf{x}=\mathbf{0}[/tex], where [tex]\mathrm{A}[/tex] is an [tex]\mathrm{m} \times \mathrm{n}[/tex] matrix and [tex]\mathbf{0}[/tex] is the zero vector in [tex]\mathbb{R}^m[/tex]. Such a system [tex]\mathrm{Ax}=\mathbf{0}[/tex] always has at least one solution, namely, [tex]x=0[/tex]. Thus a homogenous equation is always consistent.
D. False. A homogenous equation can be written in the form [tex]A \mathbf{x}=\mathbf{0}[/tex], where [tex]\mathrm{A}[/tex] is an [tex]\mathrm{m} \times \mathrm{n}[/tex] matrix and [tex]\mathbf{0}[/tex] is the zero vector in [tex]\mathbb{R}^m[/tex]. Such a system [tex]A \mathbf{x}=\mathbf{0}[/tex] always has at least one nontrivial solution. Thus a homogenous equation is always inconsistent.