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 4

_ Write −√3 + i in polar form.

Guida verificata passo dopo passo
1
Identify the complex number given: \(-\sqrt{3} + i\). Here, the real part is \(-\sqrt{3}\) and the imaginary part is \(1\).
Calculate the modulus \(r\) of the complex number using the formula \(r = \sqrt{x^2 + y^2}\), where \(x\) is the real part and \(y\) is the imaginary part. So, compute \(r = \sqrt{(-\sqrt{3})^2 + 1^2}\).
Find the argument \(\theta\) (also called the angle) using \(\theta = \tan^{-1}\left(\frac{y}{x}\right)\). Substitute \(x = -\sqrt{3}\) and \(y = 1\) to get \(\theta = \tan^{-1}\left(\frac{1}{-\sqrt{3}}\right)\).
Determine the correct quadrant for the angle \(\theta\). Since the real part is negative and the imaginary part is positive, the complex number lies in the second quadrant. Adjust the angle accordingly to reflect this quadrant.
Write the polar form of the complex number as \(r(\cos \theta + i \sin \theta)\) or equivalently \(r e^{i \theta}\), using the modulus \(r\) and the argument \(\theta\) found 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:
4m

Concetti chiave

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

Complex Numbers in Cartesian and Polar Form

A complex number can be expressed in Cartesian form as a + bi, where a is the real part and b is the imaginary part. The polar form represents the same number using a magnitude (radius) and an angle (argument), written as r(cos θ + i sin θ) or r e^{iθ}, which is useful for multiplication and division.
Video consigliato:
Percorso guidato
04:47
Complex Numbers In Polar Form

Magnitude (Modulus) of a Complex Number

The magnitude of a complex number a + bi is the distance from the origin to the point (a, b) in the complex plane, calculated as r = √(a² + b²). This value represents the radius in the polar form and is always non-negative.
Video consigliato:
Percorso guidato
4:22
Dividing Complex Numbers

Argument (Angle) of a Complex Number

The argument θ of a complex number is the angle formed with the positive real axis, found using θ = arctan(b/a). It determines the direction of the vector representing the complex number in the plane and is essential for expressing the number in polar form.
Video consigliato:
Percorso guidato
4:22
Dividing Complex Numbers