191k views
5 votes
Multiply 5i(6 - 2i).

a) 30i - 10i²
b) 12i - 10i²
c) 10i - 10i²
d) 30i + 10i²

2 Answers

1 vote

Answer:

(a)

Step-by-step explanation:

given

5i (6 - 2i) ← multiply each term in the parenthesis by 5i ( distributive law )

= 30i - 10i²

User Lai Lee
by
7.6k points
4 votes

Final answer:

The product of 5i and (6 - 2i) is 30i + 10, after distributing 5i and substituting i² with -1.

Step-by-step explanation:

To multiply the complex numbers 5i and (6 - 2i), we distribute 5i across the expression inside the parentheses:

5i × (6 - 2i) = 5i × 6 - 5i × 2i

This simplifies to:

30i - 10i²

Since i² equals -1, we replace i² with -1:

30i - 10(-1)

Which simplifies to:

30i + 10

Thus, the product of 5i and (6 - 2i) is 30i + 10, making the correct answer option 'b) 30i + 10'.

User Ssergei
by
6.9k points