All categories

4 years ago

(3-4i)(-2-21) multiply

Mathematics

1 answer:

evablogger [386]4 years ago

6 0

Answer:

-69 +92 i (here 'i' is imaginary value)

Step-by-step explanation:

step:-

Given (3-4 i)(-2-21)

on multiplication, we get

(3-4 i)(-2-21) = 3(-2) -3(21) - 4 i (-2) +4 i(21)

= -6 -63 + 8 i +84 i

= -69 +92 i

-69 + 92 i is a complex number.

real part x = -69

imaginary part y = 92

You might be interested in

An animal reserve 24,000 elk.The population is increasing at a rate of 13 percent per year.How long will it take for the populat

denpristay [2]

Answer:

9.0 years

Step-by-step explanation:

The exponential equation for the population can be written as ...

population = (initial population)(1 +growth rate)^t

p = 24000(1.13^t)

We want this to be 72000, so ...

72000 = 24000(1.13^t)

Dividing by 24000 gives ...

3 = 1.13^t

Taking logs, we have ...

log(3) = t·log(1.13)

log(3)/log(1.13) = t ≈ 8.98

It will take about 9.0 years for the elk population to reach 72,000.

6 0

3 years ago

An object is 20 cm from a concave mirror of radius of curvature 60 cm

strojnjashka [21]

The position and nature of the image are magnified,

<h3>What is the focal length?</h3>

Focal length, usually represented in millimeters (mm), is the basic description of a photographic lens.

Radius of curvature of the mirror, R = -60 cm

Focal length of the mirror, f = -30 cm

Object distance, u = -20 cm

Let v is the position of the mirror. It can be calculated as :

$\rm \dfrac{1}{v}+\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{v}=\dfrac{1}{f}-\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{-30}-\dfrac{1}{-20}\\\\\\\dfrac{1}{v}=\dfrac{-20 - (-30)}{(-30)(-20)}\\\\\dfrac{1}{v}=\dfrac{10}{(-30)(-20)}\\\\\dfrac{1}{v}=\dfrac{10}{600}\\\\\dfrac{1}{v}=\dfrac{1}{60}\\\\v=60$

The image is formed at a distance of 60 cm behind the concave mirror.

$\rm m=\dfrac{-v}{u}\\\\m=\dfrac{-60}{-30}\\\\m=2$

The image is magnified.

Hence, the position and nature of the image are magnified,

Learn more about focal length here;

https://brainly.in/question/7222487

#SPJ4

5 0

2 years ago

Can someone pls help me?

Law Incorporation [45]

Answer:

4 a

9 b

i think its a <em>answer</em>

5 0

3 years ago

Read 2 more answers

If this circle has a radius of 7.4 and m intercepted sector (shaded blue). Round answers to two decimal places.<br> Use the r bu

stealth61 [152]

Answer:

Gddghdhdhdhy heifer here early enough h her y

5 0

3 years ago

Scientists are working on a synthetic vaccine (antigen) for a particular parasite. The success of the vaccine hinges on the cha

DaniilM [7]

Answer: a) (1.34, 1.40),

b) The interval above simply implies that the least value of mean peptide score in alleles is 1.34 and the highest value is 1.40,

c) it simply implies that we are 90% sure that the interval we has the population mean.

Step-by-step explanation: The question is requiring us to construct a 90% confidence interval for mean peptide score in alleles.

From the question, we have our parameters as follows.

Sample size (n) = 44

Sample mean (x) = 1.37

Sample standard deviation (s) = 0.11

The formulae for Constructing a 90% confidence interval for population mean is given below as

u = x + Zα/2 × s/√n.... For upper tailed

u = x - Zα/2 × s/√n.... For lower tailed

Zα/2 is the critical value for a 2 tailed test.

We are using a z score for our critical value {even though we are given sample standard deviation because our sample size is greater than 30 (n=44)}.

The value for Zα/2 is gotten from a standard normal distribution table and it value here is 1.64

By substituting the parameters, we have that

For lower limit

u = 1.37 - 1.64 × 0.11/√44

u = 1.37 - 1.64 (0.0166)

u = 1.37 - 0.0272

u = 1.34

For upper limit

u = 1.37 + 1.64 × 0.11/√44

u = 1.37 + 1.64 (0.0166)

u = 1.37 + 0.0272

u = 1.40.

Hence the 90% confidence interval for mean value of peptide score in alleles is (1.34, 1.40)

The interval above simply implies that the least value of mean peptide score in alleles is 1.34 and the highest value is 1.40.

c) it simply implies that we are 90% sure that the interval we has the population mean.

3 0

3 years ago