Understanding and using complex number notation

What does i² equal?

• -1

• √-1

• 1

• -√1

What does this mean? | |

• It means that whatever number is on the outside is being divided

• It means that whatever number is inside must be the opposite. It also must be positive.

• It means that whatever number is inside is being multiplied.

What is i?

• -1

-√121

• -12

• -10

• -11

• -3

1. Simplify

• 10

• -10

• 10i

• -10i

 $i\left(i\right)$  

• -1

• i

• 1

• -i

• i

• -i

• 1

• -1

You should always substitute  $i^2$  with what number?

•  $i$  

•  $1$  

•  $-1$  

• You don't have to substitute  $i^2$  with anything. 

The square root of a negative number is negative.

• True
• False

√-9

• 3

• -3

• 81

• Not possible (for now)