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Three Cube Roots Of Unity

June 25, 2022
written by Azhar Ejaz

The cube roots of unity are the cube roots of one.

Example:

Screenshot 2022 06 25 163830

Proof:    

Let x be the cube roots of unity

Screenshot 2022 06 25 162431
Thus the three cube roots of unity are:

X3=1

X3-1=0

X3-13=0                        13=1

By using

a3 – b3= (a-b) (a2+ab+b2)

X3 -13=(x-1) (x2+x+12)

(x – 1) (x2 + x+12)=0

X – 1=0                 x2+x+1=0

X=1                            x2+x+1=0

                           By using quadratic formula

Screenshot 2022 06 25 162508 1
Thus the three cube roots of unity are:

Thus the three cube roots of unity are:

Screenshot 2022 06 25 162559
Thus the three cube roots of unity are:

We know that I am called a complex number.

    Properties of cube roots of unity

  • Each complex cube root of unity is square of the other
  • The Sum of cube roots of unity is zero
  • Product of cube roots of unity is one
  • Each complex cube root of unity is reciprocal to other
  • Each complex cube root of unity is conjugate of each   other
  • Each complex cube root of unity is the multiplicative inverses of each other
  • For anScreenshot 2022 06 25 165928 is equivalent to  one  of the cube roots of unity

Each complex cube root of unity are square of the other

Complex cube roots of unit

Screenshot 2022 06 25 162730
Thus the three cube roots of unity are:
Screenshot 2022 06 25 162753
Thus the three cube roots of unity are:
Screenshot 2022 06 25 162818
Thus the three cube roots of unity are:

Product of cube roots of unity is one

Proof:

Screenshot 2022 06 25 162911
Thus the three cube roots of unity are:
Screenshot 2022 06 25 162934
Thus the three cube roots of unity are:

Each complex cube root of unity is reciprocal of each other

Proof:

As we know

Screenshot 2022 06 25 163008
Thus the three cube roots of unity are:

Each complex cube root of unity is reciprocal to each other.

Each complex cube root of unity is conjugate of each other

Proof:

Let

Screenshot 2022 06 25 163040
Thus the three cube roots of unity are:

Hence proved

Each complex cube root of unity is conjugate of each other

For any Screenshot 2022 06 25 170604equivalent to one of the cube roots of unity.

Screenshot 2022 06 25 163112 1
Thus the three cube roots of unity are:

Frequently Asked Question-FAQs

What is the Definition of Cube Root of Unity?

The cube roots of unity are the numbers which give a result of 1 when raised to the power of 3. In other words, the cube root of unity is the cube root of 1, or 3√1.

What are the Values of Cube Roots of Unity?

The cube root of unity values are 1, −½ + i √(3/ 2), and −½ – i √(3/ 2)

What is the Sum of Cube Root of Unity?

According to the properties of the cube root of 1, the sum of its root is zero. So, 1 + ω + ω2=0.

What is the Product of Cube Root of Unity?

According to the properties Product of cube roots of unity is one