Complex numbers come into existence when the square of a number is negative because we know it very well that the square of a number will always be positive doesn’t matter whether the number is positive or negative.
In cases like or here, if we solve, we find the square of x=-1. We say that x is not real here. Generally, these types of cases are considered as Complex numbers. Complex numbers were first observed by mathematician Girolamo Cardano (1501-1575). In his book Ars Magna, he discussed the mechanics of complex numbers in details and thus he started Complex Algebra.
Standard form of Complex Numbers-
Complex numbers are defined as expressions of the form a + ib where a,b R & i =
It is denoted by Z i.e. z= a + ib.
‘a’ is called as real part of z= (Re z)
and ‘b’ is called as imaginary part of z =(Im z).
i or IOTA- iota is a unique symbol. it’s the ninth letter of Latin alphabet. It’s used to denote imaginary numbers whose square root is -1.
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