1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
gulaghasi [49]
3 years ago
14

Simplify −6(3i)(−2i) and 2(3 − i)(−2 + 4i) show work please

Mathematics
2 answers:
Xelga [282]3 years ago
4 0

Answer:

The answers are:

−6(3i)(−2i) = 36 × —1 = —36, and

2(3 – i)(−2 + 4i) = —4 + 28i

Step-by-step Explanations:

(i) −6(3i)(−2i) = —6 × 3i × —2i = —18i × —2i = 36i²

But we know that i² = —1

Therefore, −6(3i)(−2i) = 36 × —1 = —36

(ii) 2(3 – i)(−2 + 4i) = (6 — 2i)(—2 + 4i) = —12 + 24i + 4i — 8i² = —12 + 28i — 8i²

But i² = —1

Therefore, 2(3 – i)(−2 + 4i) = —12 + 28i — 8i² = —12 + 28i — 8 (—1) = —12 + 28i + 8 = —4 + 28i.

Stolb23 [73]3 years ago
3 0
I^2 = -1

-6(3i) = -18i
-18i(-2i) = 36(i^2)
36(i^2) = 36(-1)
36(-1) = -36


i^2 = -1
2(3 - i)(-2 + 4i)          :(do foil)
2(-6 + 12i +2i - 4i^2)
-2 (-6 + 14i +4)
-2(-2 + 14i)
4 -28i


4-28i is your answer

hope this helps
You might be interested in
Determine if the following relation represents a function or not.
artcher [175]

Answer:

It is a function.

Step-by-step explanation:

Functions are relations in which one domain value is assigned to exactly one range value. The x-value must not repeat in the relation set for it to be a function.

{(2,3), (4,3), (6,3), (5,9), (3,9)}

There are no repeating x-values given.

The relation should be a function.

Hope this helps.

6 0
3 years ago
(a)
lukranit [14]

Answer:

0.782

2.1%

Step-by-step explanation:

4 0
3 years ago
The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airp
motikmotik

Answer:

The 95% confidence interval for the population mean rating is (5.73, 6.95).

Step-by-step explanation:

We start by calculating the mean and standard deviation of the sample:

M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{50}(6+4+6+. . .+6)\\\\\\M=\dfrac{317}{50}\\\\\\M=6.34\\\\\\s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{49}((6-6.34)^2+(4-6.34)^2+(6-6.34)^2+. . . +(6-6.34)^2)}\\\\\\s=\sqrt{\dfrac{229.22}{49}}\\\\\\s=\sqrt{4.68}=2.16\\\\\\

We have to calculate a 95% confidence interval for the mean.

The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.

The sample mean is M=6.34.

The sample size is N=50.

When σ is not known, s divided by the square root of N is used as an estimate of σM:

s_M=\dfrac{s}{\sqrt{N}}=\dfrac{2.16}{\sqrt{50}}=\dfrac{2.16}{7.071}=0.305

The degrees of freedom for this sample size are:

df=n-1=50-1=49

The t-value for a 95% confidence interval and 49 degrees of freedom is t=2.01.

The margin of error (MOE) can be calculated as:

MOE=t\cdot s_M=2.01 \cdot 0.305=0.61

Then, the lower and upper bounds of the confidence interval are:

LL=M-t \cdot s_M = 6.34-0.61=5.73\\\\UL=M+t \cdot s_M = 6.34+0.61=6.95

The 95% confidence interval for the mean is (5.73, 6.95).

4 0
4 years ago
Can someone please answer my unanswered question on my profile please I will give brainliest
Alborosie

I will help u if u need it

7 0
3 years ago
Read 2 more answers
What number is 40% of 180?
Olin [163]

Answer:

72

Step-by-step explanation:

You can find ten percent of 180 pretty easily, it is 18 (divide by 10) then multiply by 4 to get 40%.

4 0
3 years ago
Read 2 more answers
Other questions:
  • If a snail crawls 12 centimeters per hour, how long will it take for the snail to travel 1 meter?
    14·2 answers
  • You and your friend buy 2 fruit smoothies and leave a tip. You split the total and your half comes to 3.60. What percent tip did
    6·1 answer
  • What is the equation of the line that goes through the point (0,2) and has a slope of -1​
    5·1 answer
  • Mark transferred songs from his computer onto his portable music player. He transferred 2 6/7 songs in 1 2/3 minutes. How many s
    7·2 answers
  • Can anybody help me answer this ASAP thank you
    12·1 answer
  • How many ML of a 35% acid mixture and a 95% acid mixture should be mixed to get 120 ML of a 40% acid mixture?
    12·1 answer
  • 1) Suppose a rhombus has 12 cm sides and a 30° angle. Find the distance between the pair of opposite sides.
    5·1 answer
  • Tanya have several different ways she likes to walk home. One route takes 20 minutes, two of the routes take 30 minutes, and two
    14·1 answer
  • I need help with out contex pls
    9·1 answer
  • The company is going to choose three rows in each section to win the hats. There are
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!