Name: complex numbers as vectors in polar form
Uploaded: 2024-11-21T14:54:13.000Z
Duration: 1 min 16 s
Channel: JoVE

Complex numbers, described in Cartesian coordinates, can be depicted as vectors. These can be expressed in polar form, showcasing their magnitude and angle.
When complex numbers are inputted into a function, the result is another complex number. This highlights a key feature: the function&#39;s zero point, from which the vector representation can originate.
Consider a function defined as the complex factors&#39; numerator product divided by the denominator&#39;s product.
Since each complex factor is essentially a vector, the function&#39;s magnitude at any point is calculated as the product of zero lengths divided by the product of pole lengths.
The function&#39;s angle is calculated as the sum of zero angles subtracted from the sum of pole angles. These angles are measured from the positive extension of the real axis of vectors drawn from the zero or pole of the function to the given point.
To solve a complex function at a specific point, vectors originating from the function&#39;s zeros and poles are calculated, ending at the chosen point. Substituting vector equations provides the magnitude and angle.

vector representation of complex numbers

Complex numbers, represented in Cartesian coordinates, can also be visualized as vectors. These vectors can be expressed in polar form, emphasizing their magnitude and angle. When a complex number is input into a function, the output is another complex number, highlighting the function&#39;s zero point from which the vector representation can originate.
Consider a function defined as the product of the complex factors in the numerator divided by the product of the complex factors in the denominator. Each complex factor, viewed as a vector, allows the function&#39;s magnitude at any point to be computed as the product of the magnitudes of the vectors from the zeros, divided by the product of the magnitudes of the vectors from the poles.
The angle of the function at any point is determined by the sum of the angles of the vectors from the zeros minus the sum of the angles of the vectors from the poles. These angles are measured from the positive real axis to the vectors drawn from the function&#39;s zeros or poles to the point of interest.
To solve a complex function at a specific point, vectors are drawn from each zero and pole of the function to the chosen point. The magnitudes and angles of these vectors are then used to determine the function&#39;s value at that point. The magnitude of the function is the product of the lengths of the vectors from the zeros divided by the product of the lengths of the vectors from the poles. The angle of the function is found by subtracting the sum of the angles from the poles from the sum of the angles from the zeros.
By substituting these vector equations into the function, one can obtain both the magnitude and angle of the function at the specified point. This approach allows for a comprehensive analysis of complex functions, providing insights into their behavior and properties through the use of vector representation in polar form.

Vector Representation of Complex Numbers

Complex numbers, described in Cartesian coordinates, can be depicted as vectors. These can be expressed in polar form, showcasing their magnitude and ...

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Electrical Engineering

Unit 1

Root-Locus Method

KEY TERMS AND CONCEPTS

complex numbers as vectors in polar form

Complex numbers can be shown as vectors, not just as points in Cartesian coordinates. In polar form, a vector is described by its magnitude, or length, and its angle. This makes complex numbers easier to compare by size and direction.

The same idea also helps describe complex functions. When a complex number goes into a function, the output is another complex number. The function can be viewed as having a zero point, and the vector picture starts from that point.

For a function written as a product of complex factors in the numerator divided by a product of complex factors in the denominator, each factor can be treated like a vector. The magnitude of the function at any point is found by multiplying the lengths of the vectors from the zeros and dividing by the lengths of the vectors from the poles. A zero is a point where the function can start, and a pole is a point where the denominator creates a special point in the function.

The angle of the function is found in a similar way. It is the sum of the angles from the zeros minus the sum of the angles from the poles. These angles are measured from the positive real axis to the vectors drawn from each zero or pole to the point of interest.

To solve the function at a specific point, vectors are drawn from every zero and pole to that point. Their magnitudes and angles are then used to calculate the value of the function. By replacing the function with these vector equations, both the magnitude and angle at the chosen point can be found.

Complex Numbers as Vectors in Polar Form

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key terms and concepts

Learn how complex numbers can be treated as vectors in polar form, and how zeros, poles, magnitude, and angle help evaluate complex functions.

Complex Numbers as Vectors in Polar Form | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

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Complex Numbers as Vectors in Polar Form

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