52.0k views
2 votes
(4 + 5i)(4 − 5i). answer please

2 Answers

5 votes

Answer:

41

Explanation:

edg 2020

User Irom
by
6.0k points
3 votes

Answer:

41

Explanation:

(4 + 5i)(4 − 5i)

We know that (a-b) (a+b) = a^2 -b^2

4^2 - ( 5i)^2

16 -25i^2

We know that i^2 = -1

16 -25(-1)

16+25

41

User Yongbok
by
5.6k points