Question

sum of 5-9i?

Answer 1

you have to solve for i?

Answer 2

5-9i is already a number, there's nothing more to add here. It's like adding apples to oranges here, so you can't do anything more.

Answer 3

i dont know the question just says "determine the sum of 5-9i and it's conjugate"

Answer 4

Ahh, well that's a completely different question.

(5-9i) is a complex number. The conjugate of a complex number is just everywhere you find i, change the sign from negative to positive or positive to negative.

So if you have:

(a+bi) then the conjugate is (a-bi) since I just changed the sign on the part with i.

Now if you take the example and add them up you get:

(a+bi)+(a-bi) which is equal to 2a.

Does that make sense?

Answer 5

Yes! thank you very much

Answer 6

So the answer is 10?

Answer 7

Exactly!