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

5. Angela drove to Florida for Spring Break. It took her two days. The first leg of her trip was 315.8 miles. The second leg of her trip was 152.3 miles. Around
Pioneering behavior analysts were often respected experimental psychologists who successfully and ethically intervened to reduce the suffering of, or dramatical
Please help me urgently is for a test and I need to do this homework and i don’t understand
How does hospitality affect Odysseus on his journey? Just 2-3 sentences would be great.
name 5 reasons why staying at home sucks
6. List four different types of devices that factor into the IP design:
what was it like living during the enlightenment
What does the Greek word gymno mean? large/full seed sperm bare/naked
Sixteen less than the quotient of tivice a number and three equals two.
You flip a fair coin. What is P(tails)?