Arithmetic ( Imaginary Numbers)

Secondary One Mathematics

-Lesson

In Mathematics, imaginary numbers are numbers which squares are negative real number(cannot really simplify and express them in number form) and are denoted by symbols such as "a". The imaginary unit, denoted by i or j.

As you all know, any positive number has only one (positive) square root. For your example, the square root of 4 is 2…… but what is the square root of 2?
We know that there is a way to find out. Let us use an equation that asserts this,
(Square root of 2) = Square-rooted 2 x Square-rooted 2
= 2

*As you know, Square roots are encountered geometrically, as lengths of lines. For example, square root of 2 is the length of the diagonal of a square whose sides have length of 1.

-Facts that aren't really facts

Do you know that the square root of 2=1 + ½+½ +½……?

Actually, (Square root of A) x (Square root of A)
= A
Whereas, –(Square root of A) x –(Square root of A)
still equals to = A

-Problem Solving!

In order to solve ax2 + bx + c = 0 and find the value of x,
We need to use the quadratic formula like this:
x = -b + - [Square root of (b2-4ac)]
----------------------------
2a

The next part is very "chim" as it requires strong knowledge of algebra, and alpha, beta. Ok, maybe not the latter. But nevertheless, this comes under secondary 2, I think.

-The quadratic formula

To find out the number whose square is equal to triple minus four

Quadratic Formula

A = -b + [Square root of (b2-4c)]
----------------------------
2

A = -b - [Square root of (b2-4c)]
----------------------------
2

There! All done. You have come to the end of this lesson. Come back next time for more lessons.