Graphing complex Numbers keolistravelservices.com Topical synopsis | Algebra 2 synopsis | MathBits" Teacher sources Terms that Use call Person: Donna Roberts


In 1806, J. R. Argand developed a technique for displaying complicated numbers graphically as a suggest in a unique coordinate plane. This method, referred to as the Argand chart or facility plane, creates a relationship between the x-axis (real axis) with actual numbers and the y-axis (imaginary axis) with imaginary numbers.

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In the Argand diagram, a complicated number a + bi is represented by the suggest (a,b), as shown at the left.

Graph the following complex numbers: 1. 3 + 4i(3,4)

2. -4 + 2i(-4,2)

3. 2 - 3i(2,-3)

4. 3 (which is really 3+ 0i)(3,0)

5. 4i (which is yes, really 0 + 4i)(0,4)


NOTE: Another term for "absolute value" is "modulus". When dealing with a complex number, a + bi, the state "absolute value", "modulus", and "magnitude" all describe
In the complex plane, a complicated number might be represented by a solitary point, or by the allude and a position vector(from the origin to the point). Once referenced together a vector, the hatchet "magnitude" is generally used to stand for the street from the origin (absolute value).


The Pythagorean Theorem will certainly be offered to determine the absolute worth of a complicated number.

Geometrically, the ide of "absolute value" of a actual number, such as 3 or -3, is portrayed as its distance from 0 ~ above a number line. Thus, | 3 | = 3 and also | -3 | = 3.

The "absolute value" of a complex number, is depicted as its distance from 0 in the complicated plane.

The absolute value of a complex number z = a + bi is written as | z | or | a + bi |. The is a non-negative real number identified as:


Find | z | because that :

1. z = 3 + 4i horizontal length a = 3 vertical size b = 4


2. z = -4 + 2ihorizontal length | a | = 4vertical length b = 2


The complex numbers in this Argand diagram are stood for as ordered pairs v their place vectors.

Graphical addition and individually of complicated numbers.

1. add 3 + 3i and -4 + i graphically.

Graph the two complicated numbers together vectors.

• develop a parallelogram using these 2 vectors as nearby sides. (Count turn off the horizontal and vertical lengths from one vector turn off the endpoint the the various other vector.)

• The answer come the addition is the vector creating the diagonal of the parallelogram (read from the origin).
• This brand-new vector is dubbed the resultant vector.

2. Subtract 3 + 3i from -1 + 4i graphically.

Subtraction is the procedure of adding the additive inverse. (-1 + 4i) - (3 + 3i) = (-1 + 4i) + (-3 - 3i) = -4 + i • Graph the two facility numbers as vectors.

• Graph the additive station of the number gift subtracted.

• create a parallelogram making use of the very first number and also the additive inverse.

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• The answer to the addition is the vector creating the diagonal line of the parallel (read indigenous the origin).

Topical overview | Algebra 2 rundown | keolistravelservices.com | MathBits" Teacher resources Terms the Use contact Person: Donna Roberts