Operations with Complex Numbers assessment

Which subtraction expression has the difference 1 + 4i?

(3 + 5i) - (2 + i)

Which addition expression has the sum 8 - 3i ?

(9 + 4i) + (-1 - 7i)

Subtract (3 + 2i) from (-9 - 8i).

-12 - 10i

Multiply and simplify the product. (8 - 5i)2 Select the product.

39-80i

Multiply each pair of factors. Type the product in the space provided. (6 + 3i)(6 − 3i) = (4 − 5i)(4 + 5i) = (−3 + 8i)(−3 − 8i) =

45 41 73

Find the sum of (-4 + i) and (10 - 5i).

6 - 4i

Let x = a + bi and y = c + di and z = f + gi Which statements are true? Check all of the boxes that apply.

a) x + y = y + x ⇒ commutative property of addition b) (x * y) * z = x * (y * z) ⇒ associative property of multiplication d) (x + y) + z = x + (y + z) ⇒ associative property of addition

What values of c and d would make the following expression represent a real number?i(2 + 3i)(c + di) c = 2, d = 3 c = -2, d = 3 c = 3, d = -2 c = -3, d = -2

d

Which pair of complex factors results in a real-number product? 15(-15i) 3i(1-3i) (8 + 20i)(-8 - 20i) (4+7i)(4-7i)

d

Select the correct answer from the choices given (13 + 4i) + n = 0 What is n?

-13 - 4i

Simplify each expression. Select the correct answer from the drop-down menu. −6(3i)(−2i) = 2(3 − i)(−2 + 4i) =

-36 -4 + 28i

(9 - 6i) × m = 9 - 6i What is m?

1

Multiply and simplify the product. 2i(4 - 5i) Select the product

10 + 8i

Multiply and simplify the product. (3 - 5i)(-2 + 4i) Select the product.

14 + 22i

Multiply and simplify the product. -12i × 3i Select the product

36