Linear Algebra - what is Re and Im for complex numbers?

[Arnoldjavs3]

Homework Statement

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Homework Equations

The Attempt at a Solution

I don't even know what these are, it is not outlined in my textbook. I'm assuming I am is image? But how do you calculate image even?

As far as I'm concerned I am has to do wtih linear transformations - i have no clue how to calculate it. I am looking around online but I can't even find guidance.

 

[stevendaryl]

Do you know what real and imaginary numbers are?

Here's a tutorial: https://www.mathsisfun.com/numbers/complex-numbers.html

 

[DrClaude]

Re is the real part, and I am is the imaginary part:
$$
\textrm{Re}(a + i b) = a \\
\textrm{Im}(a + i b) = b
$$
(assuming $a,b \in \mathbb{R}$).

 

[Arnoldjavs3]

Re is the real part, and I am is the imaginary part:
$$
\textrm{Re}(a + i b) = a \\
\textrm{Im}(a + i b) = b
$$
(assuming $a,b \in \mathbb{R}$).

Oh! That makes this easy then. Is this notation common then? They could have saved me the trouble of typing out a few more characters... :)

 

[DrClaude]

The notation is quite common. Another common notation is $\Re$ and $\Im$.