Finite Math Review Spring Test 1

If z1 = 4i+2 and z2 = -1-2i, then z1*z2 to which of the following?

• 6-8i

• 6+8i

• -6-8i

• -6+8i

• a correct answer is not shown

If z1 = 9+20i, then to the nearest 10th, then |z1| is equal to what value?

Three complex numbers are shown in the complex plane. Which of the following statements are true? Select all that apply.

• |z2| = |z3|

• |z2| > |z3|

• |z2| < |z3|

• |z1| > |z2|

• I

• II

• III

• IV

• It is on an axis

For each colored complex number on the complex plane, match the correct number with it's rcis(theta) value.

• 4cis(110)

• red

• 2cis(0)

• green

• 3cis(250)

• Blue

• 5cis(310)

• black

• 3cis(30)

• yellow

If the red complex number is multiplied by the blue complex number, what is the result? Write your answer as a rcis(theta) value. For example, 9cis(20)

Solve each equation. Drag the solutions to each equation to the correct equation.

Groups:

(a) z^3 = -1

,

(b) z^4 = 1

,

(c) z^5 = 1

• i

• cis(300)

• cis(90)

• cis(270)

• cis(216)

• cis(0)

• -i

• cis(60)

• cis(144)