complex multiplication 4

This figure attempts to explain the properties of complex multiplication based on basic operations of vectors. [br][br]On the left, you can see the real and imaginary parts of [math]a[/math]. Can you explain (on the right) what happens when [math]b[/math] is multiplied by the [math]a_1[/math] and [math]a_2i[/math]?

Information: complex multiplication 4