Chapter 5

Complex Numbers and Quadratic Equations

Imaginary Numbers and Powers

It is a solution to the quadratic equation or expression, x2+1 = 0, such as;

x= 0 – 1

x2 = -1

x = √-1

x = i

Therefore, an imaginary number is the part of complex number which we can write like a real number multiplied by the imaginary unit i, where i2 = -1. The imaginary number, when multiplied by itself, gives a negative value.

 

Value of Powers of i

We know, i2 = -1, let us calculate the value of ‘i’ raised to the power other imaginary numbers.

i4n = 1
i4n+1 = i
i4n+2= -1
i4n+3=-i