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An Explanation on the Power of Complex Number

In this article, we will learn about the complex numbers, power of i, complex number power formula, equality and ordering of complex numbers.

The square roots of negative numbers can be found more easily with the assistance of complex numbers. Hero of Alexandria, a Greek mathematician, made the first known reference to the concept of complex numbers in the first century B.C. when he was attempting to find the square root of a negative number. Hero’s search led him to the idea of complex numbers. However, he did nothing more than flip the negative sign to the positive position and take the numeric root value. In addition, Italian mathematician Gerolamo Cardano defined the real identity of a complex number in the 16th century. He did this while searching for the negative roots of cubic and quadratic polynomial expressions. Numerous areas of scientific study, including signal processing, electromagnetism, fluid dynamics, quantum physics, and vibration analysis, make use of complex numbers. 

Complex numbers: 

The addition of a real number and an imaginary number results in the creation of a complex number. A complex number can be written in the form a + ib and is typically denoted by the letter z. Both a and b are considered real numbers in this context. The value a, which is symbolised by the symbol Re(z), is referred to as the real portion, and the value b is referred to as the imaginary part, Im (z). Additionally, the value ib is referred to as an imaginary number. 

Power of i: 

The letter i often known as the iota, is an important symbol that can be used to represent the imaginary component of complex numbers. In addition, the iota i can be of great assistance when calculating the square root of negative values. We already know that i² equals -1, so we can use this information to determine that √-4 equals √i²4, which is equal to ±2i. The most fundamental property of a complex number is the value of the equation i² = -1. Let’s make an effort to gain a better understanding of the expanding capabilities of i. 

  • i = √-1
  • i² = -1
  • i³  = i.i² = i(-1) = -i
  • i⁴ = (i²)² = (-1)² = 1
  • i4n = 1
  • i4n + 1 = i
  • i4n + 2 = -1
  • i4n + 3 = -i 

Complex number power formula: 

Calculating the value of a complex number that has been “raised to the power of n” requires the application of a formula known as the complex number power formula. To refresh your memory, the form of a complex number is x + iy, where x and y are real values and i is an imaginary integer. The value of i ensures that i² = -1. 

Formula to calculate the power of a complex number: 

The formula for the power of complex numbers is presented in the following. 

zn = (re )n = rn einθ 

Graphing of complex numbers: 

The real and imaginary components of the complex number can be viewed as an ordered pair (Re(z), Im(z)) and can be represented as coordinates points in the euclidean plane. The real component of the complex number is the same as the real number, while the imaginary component is not. In the context of complex numbers, the euclidean plane is referred to as the complex plane or the Argand Plane, which gets its name from the mathematician Jean-Robert Argand. The complex number z is represented by its real part, a, with reference to the x-axis, and its imaginary part, ib, with reference to the y-axis. Together, these two components make up the complex number. 

Equality of complex numbers: 

The equality of real numbers and the equality of complex numbers are conceptually equivalent concepts. If the real and imaginary parts of two complex numbers, z₁ = a₁ + ib₁ and z₂ = a₂ + ib₂, are equal, then it is said that the two complex numbers, z₁ = a₁ + ib₁ and z₂ = a₂ + ib₂, are equivalent. This is because the rel part of both complex numbers is equal to a₁ = a₂ in this case. Also, the two complex numbers in the polar form are equal if and only if they have the same magnitude and their argument (angle) differs by an integral multiple of 2. This is another way of saying that the two complex numbers are the same. 

Ordering of complex numbers: 

It is impossible to put complicated numbers in any kind of order. Ordering is possible for real numbers and other number systems that are connected to them, but it is impossible for complex numbers. The structure of an ordered field is not present in the complex numbers, and there is no ordering of the complex numbers that is compatible with addition and multiplication. Additionally, the non-trivial sum of squares in an ordered field is a value less than zero, whereas the non-trivial sum of squares in a complex number is equal to i² + 1² = 0. The magnitude of a complex number can be used to determine how far away it is from the starting point in a two-dimensional argrand plane, where it can also be used to symbolise the complex number. 

Euler’s formula for complex numbers: 

According to Euler’s formula, for any real value we have e = Cosθ + iSinθ, and it represents the complex number in the coordinate plane where Cosθ is the real part and is represented with respect to the x-axis, Sinθ is the imaginary part that is represented with respect to the y-axis, and θ is the angle that is made with respect to the x-axis and the imaginary line, which is connecting the origin and the complex number In accordance with Euler’s formula and taking into consideration the functional representation of x and y, we have the following: ex + iy = ex(cosy + isiny) = excosy + iexSiny. The exponential function is decomposed into its real and imaginary components via this process. 

Conclusion: 

Imaginary numbers, which are commonly referred to as complex numbers, are utilised in a variety of real-world applications, including quadratic equations and fields such as electricity. Imaginary numbers are used in equations that do not involve the x-axis and can only be found in quadratic planes. Calculus with higher degrees of complexity makes extensive use of imaginary numbers.

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