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4 votes
Find the product of these complex numbers.
(2-3i) * (1 - i) =

2 Answers

4 votes

Answer:

- 1 - 5i

Explanation:

note that i² = - 1

Given

(2 - 3i)(1 - i) ← expand using FOIL

= 2 - 2i - 3i + 3i²

= 2 - 5i - 3

= - 1 - 5i

User Verybadalloc
by
5.1k points
2 votes

Answer: -1 - 5i

Step-by-step explanation: It's important to understand that we

can work this problem as if we were multiplying two binomials together.

In other words, we can use the F.O.I.L. method. First, Outer, Inner, Last.

The product of the first terms in each complex number is 2.

The product of the outer terms is -2i.

The product of the inner terms is -3i.

The product of the last terms is 3i².

Next, we combine our like terms. So -2i + -3i = -5i.

Also, i² is -1 so our last term is just 3(-1) or -3.

So we have 2 - 5i + (-3) or 2 - 5i - 3 which is -1 - 5i.

User Matt Schuetze
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