How do you simplify #(5i)(-8i)#?
A Complex Number is a combination of a Real Number and an Imaginary Number.
Standard Form of a Complex Number is :
In the problem given, the Real Part is unavailable.
You have just the Imaginary Part for both the complex numbers.
Multiply the complex numbers
Multiply the numerical constants first with the sign:
You need this intermediate result in the final step.
In complex numbers,
In radicals arithmetic,
Hope it helps.