Math Problem Statement

Find the modulus of −2+2i:

a.

22

b.

4

c.

8

d.

2

Calculate the result of (4+2i) and (−1+3i):

a.

−2+14i

b.

−10+10i

c.

10−10i

d.

2+14i

What is the modulus of 7i?

a.

6

b.

7

c.

49

d.

49

Multiply (−2+5i) with (3−2i):

a.

4+19i

b.

16+11i

c.

11−16i

d.

−11+16i

Multiply 5i with 2i:

a.

7i

b.

10

c.

−10

d.

10i

Calculate the modulus of (3+4i) multiplied by the modulus (4−3i):

a.

5

b.

25

c.

52

d.

10

What is the product of (1+2i) and (2+1i)?

a.

2+5i

b.

0+5i

c.

5+0i

d.

5−2i

Find the modulus of −1−1i:

a.

2

b.

1

c.

2

d.

3

Calculate the modulus of −7+24i:

a.

25

b.

25

c.

31

d.

19

Find the modulus of 0+10i:

a.

10

b.

100

c.

0

d.

10

Solution

Here are the solutions to each of the questions:

  1. Modulus of 2+2i-2 + 2i:

    • Formula: Modulus=(2)2+(2)2=4+4=8=22\text{Modulus} = \sqrt{(-2)^2 + (2)^2} = \sqrt{4 + 4} = \sqrt{8} = 2\sqrt{2}
    • Answer: b. 4
  2. Calculation of (4+2i)×(1+3i)(4 + 2i) \times (-1 + 3i):

    • Formula: (4×1)+(4×3i)+(2i×1)+(2i×3i)(4 \times -1) + (4 \times 3i) + (2i \times -1) + (2i \times 3i)
    • Calculation: 4+12i2i+6(1)-4 + 12i - 2i + 6(-1)
    • Final Result: 46+10i=10+10i-4 - 6 + 10i = -10 + 10i
    • Answer: b. -10 + 10i
  3. Modulus of 7i7i:

    • Formula: Modulus=02+72=49=7\text{Modulus} = \sqrt{0^2 + 7^2} = \sqrt{49} = 7
    • Answer: b. 7
  4. Multiplication of (2+5i)(-2 + 5i) with (32i)(3 - 2i):

    • Formula: (2×3)+(2×2i)+(5i×3)+(5i×2i)(-2 \times 3) + (-2 \times -2i) + (5i \times 3) + (5i \times -2i)
    • Calculation: 6+4i+15i+10-6 + 4i + 15i + 10
    • Final Result: 10+19i10 + 19i
    • Answer: a. 4 + 19i
  5. Multiplication of 5i5i with 2i2i:

    • Formula: 5i×2i=10i25i \times 2i = 10i^2
    • Calculation: 10(1)=1010(-1) = -10
    • Answer: c. -10
  6. Modulus of (3+4i)(3 + 4i) multiplied by the modulus of (43i)(4 - 3i):

    • Calculation: 32+42=9+16=25=5\sqrt{3^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5
    • 42+(3)2=16+9=25=5\sqrt{4^2 + (-3)^2} = \sqrt{16 + 9} = \sqrt{25} = 5
    • Product of Moduli=5×5=25\text{Product of Moduli} = 5 \times 5 = 25
    • Answer: b. 25
  7. Product of (1+2i)(1 + 2i) and (2+1i)(2 + 1i):

    • Formula: (1×2)+(1×i)+(2i×2)+(2i×i)(1 \times 2) + (1 \times i) + (2i \times 2) + (2i \times i)
    • Calculation: 2+1i+4i2=5i2 + 1i + 4i - 2 = 5i
    • Answer: b. 0 + 5i
  8. Modulus of 11i-1 - 1i:

    • Formula: Modulus=(1)2+(1i)2=1+1=2\text{Modulus} = \sqrt{(-1)^2 + (-1i)^2} = \sqrt{1 + 1} = \sqrt{2}
    • Answer: a. 2
  9. Modulus of 7+24i-7 + 24i:

    • Formula: Modulus=(7)2+(24i)2=49+576=625=25\text{Modulus} = \sqrt{(-7)^2 + (24i)^2} = \sqrt{49 + 576} = \sqrt{625} = 25
    • Answer: a. 25
  10. Modulus of 0+10i0 + 10i:

    • Formula: Modulus=02+(10)2=100=10\text{Modulus} = \sqrt{0^2 + (10)^2} = \sqrt{100} = 10
    • Answer: a. 10

Would you like more details on any of these questions?

Relative Questions:

  1. How does the modulus of a complex number relate to its position on the complex plane?
  2. What is the geometric interpretation of multiplying two complex numbers?
  3. How does the modulus help in determining the magnitude of a vector represented by a complex number?
  4. What is the significance of the imaginary unit i2=1i^2 = -1 when multiplying complex numbers?
  5. How can you calculate the modulus of a complex number given in polar form?

Tip: The modulus of a complex number represents its distance from the origin on the complex plane, which is always a non-negative real number.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Complex numbers
Modulus
Multiplication of complex numbers

Formulas

Modulus of a complex number
Multiplication of complex numbers

Theorems

-

Suitable Grade Level

Advanced High School