# Module and argument of a complex number

Consider the complex number z = a + bi and the point P that represents him.

The distance of P until the origin is called module in z, and represented by . From the highlighted rectangle triangle we have:

The angle measurement , formed by with the abscissa axis, measured counterclockwise, is called argument of the complex z. note that .

It is indicated:

 = arg (z)

Note that:

and

Example

Determine the modulus and the argument of .

Resolution:

Module:

Argument:

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