Adding, Subtracting, & Multiplying Complex Numbers

Another way to express √-1 is?

• 1

• -1

• i

• 0

A complex number can be expressed as a + bi. What does a represent?

• the real part of the complex number

• the imaginary part of the complex number

• depends on the sign of the number

• the square root of the complex number

The complex conjugate can be found by...

• Changing the sign of both a and b

• Changing the sign of a

• Changing the sign of b

• Switching the a and b values

The complex conjugate of 4 + 3i is

• 3 + 4i

• 3 - 4i

• 4 - 3i

• 4 + 3i

Simplify the expression:
 $\left(1\ +\ 5i\right)\ +\ \left(1\ -\ 5i\right)$  

•  $2\ +\ 10i$  

•  $2\ +\ 10i^2$  

•  $2$  

•  $-8$  

Simplify the expression:
 $\left(5\ +\ 4i\right)\ -\ \left(-1\ -\ 2i\right)$  

•  $6\ +6i$  

•  $4\ +\ 2i$  

•  $6\ -\ 6i$  

•  $4\ -\ 2i$  

Simplify the expression:
 $\left(8\ +\ 9i\right)\ +\ \left(4\ -\ 6i\right)$  

•  $17\ +\ 3i$  

•  $12\ +\ 3i^2$  

•  $17\ -2i$  

•  $12\ +\ 3i$  

Simplify. Write your answer in the form $a+bi$  .

 $3i\left(-1+5i\right)$  

•  $-3i+15i^2$  

•  $-1+8i$  

•  $12i$  

•  $-15-3i$  

Simplify. Write your answer in the form  $a+bi$  .

 $\left(2+4i\right)-\left(1-2i\right)$  

•  $3+2i$  

•  $1-2i$  

•  $1+6i$  

•  $10$  

Simplify. Write your answer in the form $a+bi$  .

 $\left(5-3i\right)\left(-2+4i\right)$  

•  $2+26i$  

•  $3+i$  

•  $-10-12i^2$  

•  $-22+14i$