Skip to main content
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 5, Problema 11

Plot each complex number. Then write the complex number in polar form. You may express the argument in degrees or radians. 2 + 2i

Guida verificata passo dopo passo
1
Identify the complex number given: \(2 + 2i\), where the real part is 2 and the imaginary part is 2.
Plot the complex number on the complex plane by marking the point at coordinates \((2, 2)\), where the x-axis represents the real part and the y-axis represents the imaginary part.
Calculate the modulus (or magnitude) \(r\) of the complex number using the formula \(r = \sqrt{(\text{real part})^2 + (\text{imaginary part})^2} = \sqrt{2^2 + 2^2}\).
Find the argument (or angle) \(\theta\) of the complex number using \(\theta = \tan^{-1}\left(\frac{\text{imaginary part}}{\text{real part}}\right) = \tan^{-1}\left(\frac{2}{2}\right)\), which can be expressed in degrees or radians.
Write the complex number in polar form as \(r(\cos \theta + i \sin \theta)\) or equivalently \(r \operatorname{cis} \theta\), using the values of \(r\) and \(\theta\) calculated in the previous steps.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
2m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Complex Numbers and the Complex Plane

A complex number is expressed as a + bi, where a is the real part and b is the imaginary part. It can be represented as a point or vector in the complex plane, with the x-axis as the real axis and the y-axis as the imaginary axis. Plotting involves locating the point (a, b) on this plane.
Video consigliato:
Percorso guidato
4:22
Dividing Complex Numbers

Polar Form of Complex Numbers

Polar form expresses a complex number using its magnitude (distance from origin) and argument (angle with the positive real axis). It is written as r(cos θ + i sin θ) or r∠θ, where r = √(a² + b²) and θ = arctangent(b/a). This form highlights the number's geometric properties.
Video consigliato:
Percorso guidato
04:47
Complex Numbers In Polar Form

Calculating Magnitude and Argument

The magnitude r is the length of the vector from the origin to the point (a, b), calculated by r = √(a² + b²). The argument θ is the angle formed with the positive real axis, found using θ = arctan(b/a), adjusted for the correct quadrant. These values convert rectangular form to polar form.
Video consigliato:
Percorso guidato
04:44
Finding Magnitude of a Vector