Lunar3lipse
Lunar3lipse Lunar3lipse
  • 02-03-2020
  • Mathematics
contestada

If x+yi/i = 8+ 10i, where x and y are real, what is the value of (x + yi)(x - yi)?
A 164
B 150
C. 75
D. 100

Respuesta :

amna04352
amna04352 amna04352
  • 02-03-2020

Answer:

164

Step-by-step explanation:

(x + iy)/i = 8 + 10i

(x + iy) = (8 + 10i)(i) = 8i + 10i²

= -10 + 8i

(-10 + 8i)(-10 - 8i) = (-10)² + 8² = 164

Answer Link
koyna2001 koyna2001
  • 02-03-2020

Answer:

A.164

Step-by-step explanation:

(x+yi)(x-yi) -> (8+10i)(8-10i)

rule: *(a-b)(a+b)=a^2+b^2

(8+10i)(8-10i) = 64-100i^2

rule: i^2=(-1)

64-100i^2 =  64-100(-1)

=64+100

=164

Answer Link

Otras preguntas

Explain two reasons why celebrating Holy Communion/Eucharist is important for many Christians,
Which statement best describes the subscapularis muscle?
If $20,000 is invested at 7% for 15 years, find the future value if the interest is compounded daily(365 days)
What does Newton's third law describe? A) the tendency of stationary objects to remain at rest. B) How the force applied to an object is related to a change in
what is the key idea for the story live and let die:spying and praying to stay alive?​
Which of the following resulted from the court’s ruling in Marbury v. Madison? Select one: a. The Bill of Rights became part of the Constitution b. The power o
no link no bot please right fast but right
Find the slope-intercept equation of the line that has a slope of -2 and goes through the point (5,-2).
A truck moves 60 km West, and then 80 km North, and then travels in a straight line back to its starting point. The distance travelled by the truck is ____km an
five types of conflict in the school​