Answer:
Step-by-step explanation:
Given that:
[tex]\mathtt{f(x) = ax^2 + bx + c}[/tex]
The derivative of the function of x is [tex]\mathtt{f'(x) = 2ax + b}[/tex]
Thus; f(x) is increasing when f'(x) > 0
f(x) is decreasing when f'(x) < 0
i.e
f'(x) > 0 , when b > 0 and a < 0
∴
2ax + b < 0
2ax < - b
[tex]\mathtt{x < \dfrac{-b}{2a}}[/tex]
f'(x) < 0 , when b < 0 and a > 0
2ax + b > 0
2ax > - b
[tex]\mathtt{x > \dfrac{-b}{2a}}[/tex]
What is the sum of the complex numbers −9−i−9−i and −5−i−5−i?
Answer:
The sum of the complex numbers will be - 28 - 4i
Step-by-step explanation:
We have the sum −9−i−9−i + −5−i−5−i. Let's group like elements and simplify this expression,
−9−i−9−i + −5−i−5−i ( Group like terms )
- i - i - i - i - 9 - 9 - 5 - 5 ( Add like terms )
- i - i - i - i = - 4i, - 9 - 9 = - 18, and - 5 - 5 = - 10
- 18 - 10 = - 28 ( Substitute )
Solution : - 28 - 4i
In a random sample of 64 people, 48 are classified as 'successful.' Determine the sample proportion of 'successful' people.
Answer:
The sample proportion of 'successful' people is [tex]\frac{3}{4}[/tex].
Step-by-step explanation:
The sample consist of 64 people and 48 of them are 'successful'. Hence, the proportion of 'successful' people is:
[tex]p = \frac{n}{N}[/tex]
Where:
[tex]N[/tex] - People that forms the sample, dimensionless.
[tex]n[/tex] - People classified as 'successful', dimensionless.
Given that [tex]n = 48[/tex] and [tex]N = 64[/tex], the sample proportion of 'successful' people is:
[tex]p = \frac{48}{64}[/tex]
[tex]p = \frac{3}{4}[/tex]
The sample proportion of 'successful' people is [tex]\frac{3}{4}[/tex].
A box contain 12 balls in which 4 are white 3 are blue and 5 are red.3 balls are drawn at random from the box.find the chance that all three are selected
Answer:
3/11
Step-by-step explanation:
From the above question, we have the following information
Total number of balls = 12
Number of white balls = 4
Number of blue balls = 3
Number of red balls = 5
We solve this question using combination formula
C(n, r) = nCr = n!/r!(n - r)!
We are told that 3 balls are drawn out at random.
The chance/probability of drawing out 3 balls = 12C3 = 12!/3! × (12 - 3)! = 12!/3! × 9!
= 12 × 11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1/(3 × 2 × 1) × (9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1)
= 220 ways
The chance of selecting 3 balls at random = 220
To find the chance that all the three balls are selected,
= [Chance of selecting (white ball) × Chance of selecting(blue ball) × Chance of selecting(red balls)]/ The chance/probability of drawing out 3 balls
Chance of selecting (white ball)= 4C1
Chance of selecting(blue ball) = 3C1 Chance of selecting(red balls) = 5C1
Hence,
= [4C1 × 3C1 × 5C1]/ 220
= 60/220
= 6/22
= 3/11
The chance that all three are selected is = 3/11
Salema's score on a test was 80%. If the test was worth a total of 60 points, how many points did Salema earn?
Answer:
48
Step-by-step explanation:
Do 60*.80
60 represent the total points the test was worth
.80 represents the % number
The percentage is calculated by dividing the required value by the total value and multiplying by 100.
Required percentage value = a
total value = b
Percentage = a/b x 100
100% = 60
80% = 48
The points Salema earned are 48 points.
What is a percentage?The percentage is calculated by dividing the required value by the total value and multiplying by 100.
Example:
Required percentage value = a
total value = b
Percentage = a/b x 100
Example:
50% = 50/100 = 1/2
25% = 25/100 = 1/4
20% = 20/100 = 1/5
10% = 10/100 = 1/10
We have,
Salema's score = 80%
Total score in the test = 60 points
Salema's score.
= 80% of 60 points
= 80/100 x 60
= 48
Thus,
The points Salema earned are 48 points.
Learn more about percentages here:
https://brainly.com/question/11403063
#SPJ2
suppose a chemical engineer randomly selects 3 catalysts for testing from a group of 10 catalysts, 6 of which have low acidity & 4 have high acidity. What is the probability that exactly2 lower acidic catalysts are selected?
Step-by-step explanation:
Total catalysts = 10
Probability of 2 lower acidic catalysts = 2/10 = 1/5
In how many ways can a subcommittee of 6 students be chosen from a committee which consists of 10 senior members and 12 junior members if the team must consist of 4 senior members and 2 junior members?
Answer:
The number of ways is 13860 ways
Step-by-step explanation:
Given
Senior Members = 10
Junior Members = 12
Required
Number of ways of selecting 6 students students
The question lay emphasis on the keyword selection; this implies combination
From the question, we understand that
4 students are to be selected from senior members while 2 from junior members;
The number of ways is calculated as thus;
Ways = Ways of Selecting Senior Members * Ways of Selecting Junior Members
[tex]Ways = ^{10}C_4 * ^{12}C2[/tex]
[tex]Ways = \frac{10!}{(10-4)!4!)} * \frac{12!}{(12-2)!2!)}[/tex]
[tex]Ways = \frac{10!}{(6)!4!)} * \frac{12!}{(10)!2!)}[/tex]
[tex]Ways = \frac{10 * 9 * 8 * 7 *6!}{(6! * 4*3*2*1)} * \frac{12*11*10!}{(10!*2*1)}[/tex]
[tex]Ways = \frac{10 * 9 * 8 * 7}{4*3*2*1} * \frac{12*11}{2*1}[/tex]
[tex]Ways = \frac{5040}{24} * \frac{132}{2}[/tex]
[tex]Ways = 210 * 66[/tex]
[tex]Ways = 13860[/tex]
Hence, the number of ways is 13860 ways
The histogram shows that nine students had grades of 80 or higher.
The histogram shows there were 22 students in the class.
The histogram shows there were 25 students in the class.
The histogram is symmetrical.
The histogram has a peak.
The histogram shows the data is evenly distributed.
The histogram shows a gap in the data
Answer:
bde
Step-by-step explanation:
Answer:
B: The histogram shows there were 22 students in the class.
D: The histogram is symmetrical.
E:The histogram has a peak.
F: The histogram shows the data is evenly distributed.
Step-by-step explanation:
edg 2020
A sample of 46 oil industry executives was selected to test a questionnaire. One question about environmental issues required a yes or no answer. Which of the following are possible events?a. 37 people respond *Yes." b. 29 people respond "Yes." c. 28 people respond "No." d. 50 people respond "No." e. The questionnaire fails to reach one executive.
Answer:
a. 37 people respond "Yes"
b. 29 people respond "Yes"
c. 28 people respond "No"
Step-by-step explanation:
There was a sample of 46 oil industry executives who are selected for a questionnaire. There are total 46 executives so total number of answer will be either 46 or lesser. The questionnaire responses cannot be greater than 46. The possible responses can be 37 or 29 people responses "Yes" or 28 executive responses "No"
In how many years will
The Compounds interest
onRs. 14,000 be Rs. 4, 634 at 10%
p.a?
Answer:
3 years
Step-by-step explanation:
A = P(1 + r)^t
A = I + P
A = 14,000 + 4,634 = 18,634
18,634 = 14,000(1 + 0.1)^t
18,634/14,000 = 1.1^t
log (18,634/14,000) = log 1.1^t
log (18,634/14,000) = t * log 1.1
t = [log (18,634/14000)]/(log 1.1)
t = 3
Find an equation for the line tangent to the curve at the point defined by the given value of d²y/dx².
At this point. x = 2 cos t, y = 2 sin t, t=π/4
Answer:
Step-by-step explanation:
Given:
x = 2cost,
t = (1/2)arccosx
y = 2sint
dy/dx = dy/dt . dt/dx
dy/dt = 2cost
dt/dx = -1/√(1 - x²)
dy/dx = -2cost/√(1 - x²)
Differentiate again to obtain d²y/dx²
d²y/dx² = 2sint/√(1 - x²) - 2xcost/(1 - x²)^(-3/2)
At t = π/4, we have
(√2)/√(1 - x²) - (√2)x(1 - x²)^(3/2)
The probability of the stock market going up in a single day is 51%. What is the probability that the market will go up 4 consecutive days?
Answer:
[tex]Probability = 0.068[/tex]
Step-by-step explanation:
Let P(S) represent the probability that stock market will go up in a day
Given
[tex]P(S) = 51\%[/tex]
Required
Determine the probability that stock will go up 4 consecutive days
Start by converting P(S) from percentage to decimal
[tex]P(S) = 51\%[/tex]
[tex]P(S) = \frac{51}{100}[/tex]
[tex]P(S) = 0.51[/tex]
The above expression represents the probability in a day;
For 4 days; we have:
[tex]Probability = P(S) * P(S) * P(S) * P(S)[/tex]
[tex]Probability = (P(S))^4[/tex]
Substitute 0.51 for P(S)
[tex]Probability = (0.51)^4[/tex]
[tex]Probability = 0.06765201[/tex]
[tex]Probability = 0.068[/tex] -- Approximated
Hence, the probability that stock will rise for 4 consecutive days is 0.068
someone please help it's Multiple Coordinate Transformations
Answer:
Step-by-step explanation:
Coordinates of the vertices of the given rectangle are,
A(-4, 5), B(-2, 5), C(-2,1) and D(-4, 1).
If the given rectangle ABCD is translated by 1 unit right and 4 units down,
Rule for the translation will be,
(x, y) → [(x + 1), (y - 4)]
Therefore, coordinates of A, B, C and D after translation will be,
A(-4, 5) → A'(-3, 1)
B(-2, 5) → B'(-1, 1)
C(-2, 1) → C'(-1, -3)
D(-4, 1) → D'(-3, -3)
Then A', B', C' and D' are reflected about the y-axis.
Rule for the reflection about y-axis will be,
(x, y) → (-x, y)
New coordinates after the reflection will be,
A'(-3, 1) → A"(3, 1)
B'(-1, 1) → B"(1, 1)
C'(-1, -3) → C"(1, -3)
D'(-3, -3) → D''(3, -3)
Finally these points are rotated 270° clockwise about the origin,
Rule to be followed,
(x, y) → (-y, x)
Therefore, new coordinates will be,
A"(3, 1) → A"'(-1, 3)
B"(1, 1) → B'"(-1, 1)
C"(1, -3) → C"'(3, 1)
D"(3, -3) → D"'(3, 3)
If m∠ATB = 20°, m∠BTD = 72°, and m∠CTD = 38°, what is m∠ATC?
Answer: m∠ATC = 54°
Step-by-step explanation:
Ok, we know that:
m∠ATB = 20° and m∠BTD = 72°
then we must have that the angle between A and D, is equal to the sum of the angles between A and B, and B and D, or:
m∠ATD = m∠ATB + m∠BTD = 20° + 72° = 92°
Now, we also know that m∠CTD = 38°
And the angle:
m∠ATC will be equal to the angle between A and D, minus the angle between C and D, or:
m∠ATC = m∠ATD - m∠CTD = 92° - 38° = 54°
What is similar about a line segment and a line? What is different
Answer:
A line segment has two endpoints. It contains these endpoints and all the points of the line between them. You can measure the length of a segment, but not of a line. Line segments are only a line that goes from one point to another, and lines go on forever. However, a line segment is also part of a line.
Hope this helps!
Answer:
[see below]
Step-by-step explanation:
A line is a straight path of points that has no start and no end. The line has an arrow on each end.
A line segment is part of a line. They have a start and an end. The line segments have a point on each end. You can use a line segment to make polygons and make calculations about them.
Hope this helps.
5,829 in expanded form
Answer:
5,000 + 800 + 20 + 9
Step-by-step explanation:
The definition of expanded form is to "write the value of each digit then add them together to find the sum." - study.com
That is exactly what we did above.
If we write it going up and down like below, we can pull the individual values:
5 000
8 00
2 0
9
I hope this helps!
What is the area of the house (including the drawing room, TV room, balcony, hallway, kitchen, and bedroom)?
Answer:
A
Step-by-step explanation:
Listed below are systolic blood pressure measurements (mm Hg) taken from the right and left arms of the same woman. Assume that the paired sample data is a simple random sample and that the differences have a distribution that is approximately normal. Use a 0.05 significance level to test for a difference between the measurements from the two arms. What can be concluded?
Right_arm(mm_Hg) Left_arm(mm_Hg)
149 166
136 179
129 190
137 148
139 138
Data was entered in SPSS using the paired t-test approach!!
a. In this example, μd is the mean value of the differences d for the population of all pairs of data, where each individual difference d is defined as the measurement from the right arm minus the measurement from the left arm. What are the null and alternative hypotheses for the hypothesis test?
b.) Identify the test statistic.
c.) Identify the P-value.
d.) What is the conclusion based on the hypothesis test?
Answer:
There is a significant difference in the systolic blood pressure measurements between the two arms.
Step-by-step explanation:
The dependent t-test (also known as the paired t-test or paired samples t-test) compares the two means associated groups to conclude if there is a statistically significant difference amid these two means.
In this case a paired t-test is used to determine whether there is a difference in the systolic blood pressure measurements between the two arms.
The SPSS output is attached below.
(a)
The hypothesis for the test can be defined as follows:
H₀: There is no difference in the systolic blood pressure measurements between the two arms, i.e. d = 0.
Hₐ: There is a significant difference in the systolic blood pressure measurements between the two arms, i.e. d ≠ 0.
(b)
Consider the SPSS output.
The test statistic value is t = 0.871.
(c)
Consider the SPSS output.
The p-value of the test is:
p-value = 0.433.
(d)
The significance level of the test is, α = 0.05.
Decision rule:
If the p-value of the test is less than the significance level then the null hypothesis will be rejected and vice-versa.
p-value = 0.433 > α = 0.05
The null hypothesis will not be rejected at 5% level of significance.
Conclusion:
Thus, it can be concluded that there is a significant difference in the systolic blood pressure measurements between the two arms.
What number must be added to the expression below to complete the square? x2-5x
Answer:
6.25
Step-by-step explanation:
(x-a)^2=x^2-2ax+a^2
2a=5
a=2.5
2.5 ^ 2 = 6.25
if 2x-7 is 5 more than x+4, what is the value of 3x+5
Answer:
53
Step-by-step explanation:
Let's start with the given relation:
2x -7 = (x+4) +5
x = 16 . . . . . . . . . add 7-x
3x +5 = 3(16) +5 = 53 . . . . . multiply by 3 and add 5
The value of 3x+5 is 53.
Graph the following set of parametric equations on your calculator and select the matching graph.
Answer:
Graph 2
Step-by-step explanation:
The equation x = t² - 3 is represented by exponential growth, ( t² ) so it's graph will be similar to the first graph, graph 1, in our options. Then again we have to consider the equation y = √t - 2, which will be similar to graph 4, but with a greater slope. This leaves us with a solution of graph b.
please solve quick
Answer:
x = 5
AC = 6
DC = 8
Step-by-step explanation:
∆ABC ~ ∆CDE
Therefore, [tex] \frac{AB}{ED} = \frac{AC}{DC} [/tex]
AB = 3
ED = 4
AC = x + 1
DC = x + 3
Plug in the values and solve for x:
[tex] \frac{3}{4} = \frac{x + 1}{x + 3} [/tex]
Cross multiply
[tex] 3(x + 3) = 4(x + 1) [/tex]
[tex] 3x + 9 = 4x + 4 [/tex]
[tex] 3x - 4x = -9 + 4 [/tex]
[tex] -x = -5 [/tex]
[tex] x = 5 [/tex]
Plug in the value of x and find AC and DC
AC = x + 1 = 5 + 1 = 6
DC = x + 3 = 5 + 3 = 8
Your investment club has only two stocks in its portfolio. $25,000 is invested in a stock with a beta of 0.8, and $40,000 is invested in a stock with a beta of 1.7. What is the portfolio's beta? Do not round intermediate calculations. Round your answer to two decimal places.
Answer:
The portfolio beta is [tex]\alpha = 1.354[/tex]
Step-by-step explanation:
From the question we are told that
The first investment is [tex]i_1 = \$ 25,000[/tex]
The first beta is [tex]k = 0.8[/tex]
The second investment is [tex]i_2 = \$ 40,000[/tex]
The second beta is [tex]w = 1.7[/tex]
Generally the portfolio beta is mathematically represented as
[tex]\alpha = \frac{ i_1 * k + i_2 * w }{ i_1 + i_2}[/tex]
substituting values
[tex]\alpha = \frac{ (25000 * 0.8) + ( 40000* 1.7 ) }{40000 + 25000}[/tex]
[tex]\alpha = 1.354[/tex]
Century Roofing is thinking of opening a new warehouse, and the key data are shown below. The company owns the building that would be used, and it could sell it for $100,000 after taxes if it decides not to open the new warehouse. The equipment for the project would be depreciated by the straight-line method over the project's 3-year life, after which it would be worth nothing and thus it would have a zero salvage value. No new working capital would be required, and revenues and other operating costs would be constant over the project's 3-year life. What is the project's NPV? (Hint: Cash flows are constant in Years 1-3.)
Question Completion:
WACC = 10.0%
Opportunity cost = $100,000
Net equipment cost (depreciable basis) = $65,000
Straight-line deprec. rate for equipment = 33.333%
Sales revenues, each year = $123,000
Operating costs (excl. deprec.), each year = $25,000
Tax rate = 35%
Answer:
Century Roofing
Project's NPV is: ($6,578)
Step-by-step explanation:
a) Data and Calculations:
WACC = 10.0%
Opportunity cost = $100,000
Net equipment cost (depreciable basis) = $65,000
Straight-line deprec. rate for equipment = 33.333%
Sales revenues, each year = $123,000
Operating costs (excl. deprec.), each year = $25,000
Tax rate = 35%
Cash outflow in year 0 = $165,000 (Opportunity and new equipment costs)
Annual Cash inflow = $123,000 - $25,000 - $34,300 = $63,700
PV of annuity for 3 years at 10% = $158,422 ($63,700 x 2.487)
NPV = Cash inflow minus Cash outflow
= $158,422 - $165,000
= ($6,578)
Negative NPV
b) Since Century Roofing could have realized $100,000 from the sale of the building if it decides not to open the new warehouse, this opportunity cost is factored into the calculation of the Net Present Value. It becomes a present cash outflow. Century Roofing's opportunity cost is defined as the loss of $100,000 being the future return from the best alternative project when it chooses to build the new warehouse instead of selling off the building.
Need help please! what is the total length of a 20 mm steel coiled like a spring with a 16 turns and an outer diameter of 600 mm. pitch is 300 mm. Show your solution please coz i don't really know how to do it! thanks
Answer:
L = 29,550 mm (as per BS8110 the length is to the nearest 25)
Step-by-step explanation:
Lets make it so simple and easy.
Let A = 600mm
Let B = 300mm
Let C = 16 as number turns
Let d = 20mm
L = [tex]\sqrt{(3.14 * (600 - 20))^{2} + 300^{2}[/tex] x 16
L = 29,550 mm (as per BS8110 the length is to the nearest 25)
Q-The general solution of inequality cos 2 x≤- sin x is
Answer:
x∈[2nπ−5π/6, 2nπ−π/6]∪{(4n+1)π/2}, n ϵ I
Step-by-step explanation:
1−2sin2 x≤−sin x ⇒ (2sin x+1)(sin x−1)≥0
sin x≤−1/2 or sin x≥1
−5π/6+2nπ≤x≤−π/6+2nπ or , n ϵ I x=(4n+1)π/2, n ϵ I⇒ -5π6+2nπ≤x≤-π6+2nπ or , n ϵ I x=4n+1π2, n ϵ I (as sin x = 1 is valid only)
In general⇒ In general x∈[2nπ−5π/6, 2nπ−π/6]∪{(4n+1)π/2}, n ϵ I
In politics, marketing, etc. we often want to estimate a percentage or proportion p. One calculation in statistical polling is the margin of error - the largest (reasonble) error that the poll could have. For example, a poll result of 72% with a margin of error of 4% indicates that p is most likely to be between 68% and 76% (72% minus 4% to 72% plus 4%). In a (made-up) poll, the proportion of people who like dark chocolate more than milk chocolate was 35% with a margin of error of 2.5%. Describe the conclusion about p using an absolute value inequality.
Answer:
The conclusion about p using an absolute value inequality is
[tex]0.325 < p < 0.375[/tex]
Step-by-step explanation:
From the question we are told that
The sample proportion is [tex]\r p = 0.35[/tex]
The margin of error is [tex]E = 0.025[/tex]
The confidence interval is mathematically represented as
[tex]\r p -E < p < \r p +E[/tex]
=> [tex]0.35 - 0.025 < p < 0.35 + 0.025[/tex]
=> [tex]0.325 < p < 0.375[/tex]
Which of the following is equivalent to –2i(6 – 7i)?
Answer:
[tex]\boxed{\sf \bf \ \ -2i(6-7i)=-14-12i \ \ }[/tex]
Step-by-step explanation:
Hello, please consider the following.
[tex]-2i(6-7i)=-12i+14i^2=-14-12i[/tex]
Hope this helps.
Do not hesitate if you need further explanation.
Thank you
Answer:
A
Step-by-step explanation:
Answer = A
The rate at which an assembly line workers efficiency E (expressed as a percent) changes with respect to time t is given by E'(t) = 75 - 6t, where t is the number of hours since the workers shift began. Assuming that E(1) = 92, find E(t).
By the fundamental theorem of calculus,
[tex]E(t)=E(1)+\displaystyle\int_1^t E'(u)\,\mathrm du[/tex]
So we have
[tex]E(t)=92+\displaystyle\int_1^t(75-6u)\,\mathrm du[/tex]
[tex]E(t)=92+(75u-3u^2)\bigg|_1^t[/tex]
[tex]E(t)=20 + 75 t - 3 t^2[/tex]
What is the volume of a sphere, to the nearest cubic inch, if the radius equals 5 inches? Use π = 3.14.
Answer:
V = 523 in^3
Step-by-step explanation:
The volume of a sphere is given by
V = 4/3 pi r^3
V = 4/3 ( 3.14) * 5^3
V = 523.33333repeating
Rounding to the nearest inch^3
V = 523 in^3
Answer:
[tex] 523.6 {in}^{3} [/tex]
Step-by-step explanation:
[tex]v = \frac{4}{3} \pi {r}^{3} \\ = \frac{4}{3} \pi \times 5 \times 5 \times 5 \\ = 523.6 {in}^{3} [/tex]
If f is a function that f(f(x)) = 2x² + 1, which is the value of f(f(f(f(3)))? Please help!
[tex]f(f(3))=2\cdot3^2+1=19\\f(f(f(f(3))))=2\cdot19^2+1=723[/tex]
