# Inverse of complex number

• plexus0208
In summary, the inverse of a complex number is a number that, when multiplied by the original complex number, results in a product of 1. To find the inverse of a complex number, you need to write the number in the form of a + bi, find its conjugate, and multiply them together. The inverse of a complex number is important in solving equations and operations involving complex numbers. It is always a real number and is the same as its reciprocal.

#### plexus0208

How does taking the multiplicative inverse (reciprocal) of a complex number change its magnitude and argument?

A complex number z, when inverted, will have its magnitude also inverted, $$|z^{-1}| = \frac{1}{|z|}$$ and its argument will become its supplement, $$arg(z^{-1}) = \pi - arg(z)$$

Why don't you try proving that?

This does not itself have anything to do with "differential equations" so I am moving it to "general mathematics".

I think "supplement" is wrong. The reciprocal of 1 is 1, but the supplement of 0 is not 0.

Hey,
I think that arg(z^-1) = - arg (z)

## 1. What is the inverse of a complex number?

The inverse of a complex number is a number that, when multiplied by the original complex number, results in a product of 1. It is similar to the concept of multiplicative inverse in regular numbers, where a number multiplied by its inverse gives a product of 1.

## 2. How do you find the inverse of a complex number?

To find the inverse of a complex number, you need to follow these steps:

1. Write the complex number in the form a + bi, where a is the real part and b is the imaginary part.
2. Find the conjugate of the complex number by changing the sign of the imaginary part. For example, the conjugate of a + bi is a - bi.
3. Multiply the original complex number by its conjugate.
4. The resulting product will be a real number, which is the inverse of the original complex number.

## 3. What is the significance of the inverse of a complex number?

The inverse of a complex number is important in solving equations involving complex numbers. It is also used in operations involving complex numbers, such as division and finding roots.

## 4. Can the inverse of a complex number be a complex number?

No, the inverse of a complex number is always a real number. This is because the product of a complex number and its conjugate will always result in a real number.

## 5. Is the inverse of a complex number the same as its reciprocal?

Yes, the inverse of a complex number is the same as its reciprocal. This is because the concept of inverse and reciprocal are similar, where a number multiplied by its inverse or reciprocal gives a product of 1.