Simplify 2(3 - 4i)

Step by step

The question

Question: work out 2(3 − 4i).

No real number times itself is negative.

So we use a new number: i, the square root of minus 1.

So i squared is minus 1.

1 Multiply each part

The number in front times each part.

2 times 3 is 6.

2 times −4i is −8i.

We write all the parts.

So the answer is 6 − 8i.

2 Check

Let's check: multiply the other way round, (3 − 4i) × 2.

Each part times each part again.

We get 6 − 8i again.

So the answer is right!

Let's look back.

First: multiply each part.

Last: check.