Adding Imaginary Numbers

To add two imaginary numbers, you simply add their imaginary parts together. $$ (0,a) + (0,b) = (0,a+b) $$ When expressed in algebraic form, where (0,b)=bi, the addition looks like this: $$ a i + b i = (a+b)i $$

Example

Consider the following two imaginary numbers:

$$ (0,2)=2i $$ $$ (0,3)=3i $$

Their sum is (0,5).

$$ (0,2)+(0,3)=(0,2+3)=(0,5) $$

Expressing the imaginary numbers in algebraic form gives the same result:

$$ 2i+3i = (2+3)i = 5i $$

Note: The imaginary number 5i is another way of representing (0,5). Since the imaginary unit i is defined as a constant, i=(0,1), we can write: $$ 5i = 5 \cdot (0,1) = (5 \cdot 0, 5 \cdot 1) = (0,5) $$

And so on.

 

 
 

Please feel free to point out any errors or typos, or share suggestions to improve these notes. English isn't my first language, so if you notice any mistakes, let me know, and I'll be sure to fix them.

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