Category:Examples of Use of Equation for Line through Two Points in Complex Plane

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This category contains examples of use of Equation for Line through Two Points in Complex Plane.

Let $z_1, z_2 \in \C$ be complex numbers.

Let $L$ be a straight line through $z_1$ and $z_2$ in the complex plane.


Formulation 1

$L$ can be expressed by the equation:

$\map \arg {\dfrac {z - z_1} {z_2 - z_1} } = 0$


Parametric Form $1$

$L$ can be expressed by the equation:

$z = z_1 + t \paren {z_2 - z_1}$

or:

$z = \paren {1 - t} z_1 + t z_2$


This form of $L$ is known as the parametric form, where $t$ is the parameter.


Parametric Form $2$

$L$ can be expressed by the equations:

\(\ds x - x_1\) \(=\) \(\ds t \paren {x_2 - x_1}\)
\(\ds y - y_1\) \(=\) \(\ds t \paren {y_2 - y_1}\)


These are the parametric equations of $L$, where $t$ is the parameter.


Symmetric Form

$L$ can be expressed by the equation:

$z = \dfrac {m z_1 + n z_2} {m + n}$


This form of $L$ is known as the symmetric form.