Sample of 12 students, 9 reported falling asleep in class, which is much higher than we would expect based on the survey results.So, we can say that this is an unusually high number of students who have fallen asleep in class.
It is an unusually high number of students who have fallen asleep in class. There are a couple of reasons why we can say that. Let's consider the survey first:In a survey of 4,513 college students, 46% of the respondents reported falling asleep in class due to poor sleep. This means that approximately 2,074 students reported falling asleep in class. We can calculate this by multiplying the total number of students (4,513) by the percentage of students who reported falling asleep in class (46%):4513 * 0.46 = 2074So, out of 4,513 students, we can expect around 2,074 to report falling asleep in class.Now let's consider the random sample of 12 students from the dormitory:You randomly sample 12 students in your dormitory, and 9 state that they fell asleep in class during the last week due to poor sleep.Relative to the survey results, this is an unusually high number of students. Out of the 12 students sampled, we can expect around 46% (since that was the percentage in the survey) to report falling asleep in class, which is approximately 6 students. However, in this sample of 12 students, 9 reported falling asleep in class, which is much higher than we would expect based on the survey results.So, we can say that this is an unusually high number of students who have fallen asleep in class.
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Note: In the following problem, it is important to show all the steps used to get your answers.
Suppose an imaginary closed economy is characterized by the following:
C = c0 + c1 (Y − T)
T = 300 I = 400 G = 400
C is consumption, Y and YD are, respectively, income and disposable income, T is the level
of taxes, I and G, are, respectively, private investment, and government spending.
c0 and c1 are, respectively, autonomous consumption and the marginal propensity to con-
sume; their values are unknown. However, the expression for private saving, S, is as specified
below.
S = 0.5Y − 500
1. Find the equilibrium values of GDP, consumption, disposable income, and private saving.
(5 points)
2. Find the expression of the investment multiplier in terms of c0 and/or c1. (3 points)
3. Find the values of c0 and c1 and the value of the investment multiplier (Hint: you’ll prob-
ably find c0 is equal to an even number, which is multiple of 2). (5 points)
4. From this question on, you must use when needed the values of c0 and c1 found in the pre-
vious question. Suppose now that the government tax revenue, T, has both autonomous
and endogenous components, in the sense that the tax level depends on the level of in-
come.
T = t0 + t1Y
t0 is the autonomous tax level, and t1 is the marginal tax rate.
Given the values of private investment and government spending mentioned above, find
the expression for the equilibrium GDP in terms of c0, c1, t0 and t1. (4 points)
5. Assuming that t0 = 200 find the value of the marginal tax rate that will yield the same
level of equilibrium GDP as the one obtained (1). (4 points)
6. Find the expression for the investment multiplier in terms of c1and t1 and possibly c0, and
t0. (4 points)
7. Assume now that private investment, I, increases by 50. Find the change in GDP, ∆Y,
induced by the change in investment, ∆I = 50. (4 points)
8. The government does not like the change in GDP induced by the increase in private in-
vestment. It wants to bring it back to the level found in Question (1). For that purpose, it
has the options to change its spending or to change taxes.
(a) If the government changes its spending alone, find the level of ∆G required to coun-
teract the effect on GDP of the fall in investment. (4 points)
(b) If the government changes instead the level of its autonomous taxes alone, find the
level of ∆t0 required to counteract the effect on GDP of the fall in investment. Explain
what happened. (4 points)
(c) How does ∆G compare to ∆t0? Explain the difference, if there is any. (4 points)
(d) In which direction should the government change its marginal tax rate, t1 (increase
or decrease), if it uses it as the sole policy instrument to counteract the effect of the
change in investment? Explain intuitively your answer. (4 points)
Only need to answer 5-8 questions!!!!
5. Assuming that t0 = 200 find the value of the marginal tax rate that will yield the same level of equilibrium GDP as the one obtained
(1). Solution: Given, T = t0 + t1Y and T = 300
Substituting the given values, we get300 = 200 + t1YGDP, Y = C + I + G + X - M
where, Y = GDP; C = consumption; I = private investment; G = government spending; X = exports; M = imports
We know, C = c0 + c1 (Y − T) Disposable income, YD = Y − T
So, C = c0 + c1 (Y − T) = c0 + c1YD
From the question, S = 0.5Y − 500
We know that, private saving, S = Y − C − T
So, Y − C − T = 0.5Y − 500 ⇒ 0.5Y = C + T + 500
Putting the values,
0.5Y = (c0 + c1YD) + T + 500 ⇒ 0.5Y = (c0 + c1(Y - T)) + T + 500 ⇒ 0.5Y = c0 + c1Y - c1T + T + 500
Solving the above expression, we get
0.5Y - c1Y = c0 - 0.5T + 500 ⇒ 0.5(1-c1)Y = c0 - 0.5T + 500
Hence, Y = (c0 - 0.5T + 500) / (0.5 - c1)
Again, from the question, Y = C + I + G + X - M
Substituting the values we get,
(c0 + c1(Y − T)) + 400 = I + 400 + Y - 500 + X - X0.5Y − 500 + 400 = I + 300 + X − G ⇒ 0.5Y + I = 1200 + G + X
Assuming equilibrium GDP Y = Y*, private investment I = I*, government spending G = G* and net exports X = X*, so0.5Y* + I* = 1200 + G* + X*
Now, from the given information of S, we have S = Y* − C* − T.
Substituting for C* from the equation above, we get S = Y* − (c0 + c1(Y* − T)) − T ⇒ S = Y* − c0 − c1Y* + c1T − T
Substituting for Y* from above, we have S = ((c0 - 0.5T + 500) / (0.5 - c1)) - c0 - c1[((c0 - 0.5T + 500) / (0.5 - c1))] + c1T - T
Now, we need to find the value of t1 when t0 = 200. For this, we need to substitute the value of t0 and Y* in T = t0 + t1YSo, 300 = 200 + t1Y* ⇒ t1 = (300 - 200) / Y* ⇒ t1 = 0.1
Therefore, the value of the marginal tax rate t1 is 0.1.
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Codification and Decodification let F = Z2. Consider the code
C = {000000, 001111, 110011, 111100, 101010}.
(a) Show that C is not a linear code.
b) Add words to C to form a new code C' that is linear.
c) Find a base of C'
Main Answer: The base of C' is {0110, 1001, 1100, 0011}.
Supporting Explanation: In a communication system, codification and decodification are used to encode and decode messages. C is the code for the message, where C={0000, 1100, 1010, 0110, 0101, 0011, 1001, 1111}. The code is a binary code since F=Z2. C' is the dual code of C. The codewords in C' are orthogonal to those in C. A basis for C' can be determined by finding a generator matrix for C'. Thus, the generator matrix for C is the parity check matrix for C'. A generator matrix for C is given as, G = [I | P] where P is the parity check matrix. The parity check matrix for C can be determined as, P = [-AT | Im-k]. Therefore, P = [0101; 1010; 1111].The rows of C' correspond to the columns of P. Thus, a basis for C' is {0110, 1001, 1100, 0011}.
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Help me please!! If you do you will get 25 points :)
Answer:
24 units by 15 units
Step-by-step explanation: To find how many units the length and width are, divide each by 5:
120/5 = 24
75/5= 15
For every 5 feet, there is 1 unit .
what is the equation for a Vertical Shift 5 units up?
consider the vectors v1, v2, v3 in r2 (sketched in the accompanying figure). vectors v1 and v2 are parallel. how many solutions x, y does the system xv1 yv2 = v3 have? argue geometrically.
There is exactly one solution if v3 lies on this line, and no solution otherwise.
Given: vectors v1, v2, v3 in R2
We know that the vectors v1 and v2 are parallel, and we are asked to find the number of solutions of the system xv1 + yv2 = v3. We will argue geometrically.
Let us say that v1 and v2 are not equal to zero and are parallel to the x-axis. We can then write:
v1 = (a, 0)
v2 = (b, 0)
where a and b are nonzero constants. Since v1 and v2 are parallel, their cross-product is zero:
v1 × v2 = a*0 - 0*b = 0
This means that v1 and v2 are linearly dependent. Thus, we can express v2 as a scalar multiple of v1:
v2 = k*v1
where k is a nonzero constant. We can then substitute these expressions into the system and solve for x and y:
xv1 + yv2 = v3
xv1 + y(k*v1) = v3
(x + ky)v1 = v3
Since v1 is nonzero, the equation has a unique solution if and only if (x + ky) is nonzero. But (x + ky) is zero if and only if x = -ky, which is the equation of a line passing through the origin and perpendicular to v1 and v2. Thus, there is exactly one solution if v3 lies on this line, and no solution otherwise.
To see this geometrically, we can sketch the vectors v1, v2, and v3, and the line passing through the origin and perpendicular to v1 and v2. If v3 lies on this line, then there is exactly one solution, which corresponds to the intersection of the line and the vector v3. If v3 does not lie on this line, then there is no solution, since the line does not pass through v3.
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a rectangle is inscribed with its base on the x-axis and its upper corners on the parabola y = 2 − x 2 . what are the dimensions of such a rectangle with the greatest possible area?
To find the dimensions of the rectangle with the greatest possible area inscribed in the parabola y = 2 - x^2, we need to maximize the area function by determining the x-coordinate where the derivative of the area function is zero.
Let's consider a rectangle with its base on the x-axis, which means its height will be given by the y-coordinate of the parabola. The width of the rectangle will be twice the x-coordinate. Therefore, the area of the rectangle is given by A = 2x(2 - x^2).
To maximize the area, we take the derivative of A with respect to x and set it equal to zero to find critical points. Differentiating A, we get dA/dx = 4 - 6x^2.
Setting 4 - 6x^2 = 0 and solving for x, we find x = ±√(2/3).
Since the rectangle is inscribed, we consider the positive value of x. Therefore, the x-coordinate of the upper corner of the rectangle is √(2/3). Plugging this value back into the equation of the parabola, we get y = 2 - (√(2/3))^2 = 2 - 2/3 = 4/3.
Hence, the dimensions of the rectangle with the greatest possible area are a base of length 2√(2/3) on the x-axis and a height of 4/3.
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2. Suppose 250 randomly selected people are surveyed to determine if they own a tablet. Of the 250 surveyed, 98 reported owning a tablet. Using a 95% confidence level, compute a confidence interval estimate for the true proportion of people who own tablets.
A. With 95% confidence, we say that the proportion of people who own tables is between 32% and 98%.
B. With 95% confidence, we say that the proportion of people who own tables is between 32% and 99%.
C. With 95% confidence, we say that the proportion of people who own tables is between 33% and 98%.
D. With 95% confidence, we say that the proportion of people who own tables is between 33% and 99%.
Solution:
Given that a random-sample of 250 people is surveyed to determine if they own a tablet, where 98 people own a tablet.
We have to find a confidence interval estimate for the true proportion of people who own tablets using a 95% confidence-level.
The formula to compute confidence interval estimate is given by;
[tex]CI = p \pm Z_{\frac{\alpha}{2}}\sqrt{\frac{p(1-p)}{n}}[/tex]
Where;[tex]p[/tex] = Sample proportion[tex]Z_{\frac{\alpha}{2}}[/tex] = Critical value of Z at [tex]\frac{\alpha}{2}[/tex][tex]n[/tex] = Sample size
From the given data,Sample proportion, [tex]p = \frac{98}{250} = 0.392[/tex]
Level of Confidence, [tex]C= 95%[/tex]
As level of significance [tex]\alpha = (1-C) = 0.05[/tex]So, [tex]\frac{\alpha}{2} = \frac{0.05}{2} = 0.025[/tex]
Sample size, [tex]n = 250[/tex]
Now, we need to find the critical value of [tex]Z_{0.025}[/tex] such that the area to its right in the z-distribution is 0.025.Z-table shows the values of Z for given probabilities.
The closest value to 0.025 is 1.96. So, we can take [tex]Z_{0.025} = 1.96[/tex].
Therefore, the confidence interval estimate for the true proportion of people who own tablets using a 95% confidence level is given as;[tex]CI = 0.392 \pm 1.96\sqrt{\frac{0.392(1-0.392)}{250}}[/tex][tex]\Rightarrow CI = 0.392 \pm 0.067[/tex]
So, the lower limit of the interval is obtained as;
[tex]0.392 - 0.067 = 0.325[/tex]
And the upper limit of the interval is obtained as;
[tex]0.392 + 0.067 = 0.459[/tex]
Therefore, with 95% confidence, we say that the proportion of people who own tablets is between 32.5% and 45.9%.
The correct option is (A).
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Find the area of this kite.
3 m
5 m
6 m
5 m
Answer:
450m
Step-by-step explanation:
PLS hurry!! I'LL MARK BRAINLIEST!
Answer:
A. 5+x-12=2x-7
-7+x+2x-7
x=2x
x-2x=0
-x=0-> x=0
B.
when X=-0.5
5+(-0.5)-12=2 (-0.5)-7
-7.5=-8 (answer does not work)
when X=0
5+0-12=2(0)-7
-7=-7 (answer works)
when x=1
5+1-12=2(1)-7
18=-5 (answer does not work)
Step-by-step explanation:
Answer:
[tex]x=0[/tex]
Step-by-step explanation:
A) From this case you would need to narrow down the whole equation...
Like this: [tex]5+x-12=2x-7[/tex] → [tex]x-7=2x-7[/tex] → [tex]x=0[/tex]
B) To prove that one of these numbers solve the equation, we would have to check it ourselves.
Like this: [tex]5+(-0.5)-12=2(-0.5)-7[/tex] → [tex]-7.5=-8[/tex] (SO THIS WON'T WORK)
[tex]5+0-12=2*0-7[/tex] → [tex]0=0[/tex] (THIS WORKS!)
[tex]5+1-12=2(1)-7[/tex] → [tex]-6=-5[/tex] (NOR DOES THIS WORK)
Therefore: [tex]x=0[/tex] will work to solve the equation correctly
Simplify 7a - 3(b - a)
Answer:
10a-3b is your answer
Step-by-step explanation:
7a - 3(b - a)
7a-3b+3a
10a-3b
Please help, I can’t figure this answer out and I’m really struggling on it!
The exponent on the (x - 1) term include the following: A. 3.
What is an exponent?In Mathematics, an exponent is a mathematical operation that is commonly used in conjunction with an algebraic equation or expression, in order to raise a given quantity to the power of another.
Mathematically, an exponent can be represented or modeled by this mathematical expression;
bⁿ
Where:
the variables b and n are numbers (numerical values), letters, or an algebraic expression.n is known as a superscript or power.By critically observing the graph of this polynomial function, we can logically deduce that it has a zero of multiplicity 3 at x = 1, a zero of multiplicity 1 at x = 3, and zero of multiplicity 2 at x = 4;
x = 1 ⇒ x - 1 = 0.
(x - 1)³
x = 3 ⇒ x - 3 = 0.
(x - 3)
x = 4 ⇒ x - 4 = 0.
(x - 4)²
Therefore, the required polynomial function is given by;
P(x) = (x - 1)³(x - 3)(x - 4)²
Exponent of (x - 1)³ = 3.
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what is the measure of angle A?
Answer:
122
Step-by-step explanation:
180 - (43 + 15)
Answer:
The answer is 2.86
Step-by-step explanation:
you just have to divide 43 by 15
In ΔGHI, h = 650 cm, i = 130 cm and ∠G=72°. Find the area of ΔGHI, to the nearest square centimeter.
Answer:
84500 is the correct answer
Answer:
40182 delta math
Step-by-step explanation:
The distribution of actual weights of wedges of cheddar cheese produced at a dairy is normal with a mean of 10.2 ounces and a standard deviation of 0.2 ounces. (Round all answers to 4 decimal places, if needed.)
(a) The probability that a randomly chosen wedge of cheddar cheese is greater than 10.14 is .
(b) If a sample of 16 is randomly chosen, then the distribution of the sample mean weight is approximately normal not normal left-skewed right-skewed with a mean of ? and a standard deviation of .
(c) The probability that the sample mean weight of this sample of 16 is less than 10.14 is .
(d) The probability that the sample mean weight of this sample of 16 is greater than 10.14 is .
(e) The probability that the sample mean weight of this sample of 16 is between 10.14 and 10.3 is .
(f) There is only a 7% chance that the average weight of a sample of these 16 cheese wedges will be below .
(a) The probability that a randomly chosen wedge of cheddar cheese is greater than 10.14 is found using the standard normal distribution as follows:
P(Z > z) = P(Z > (10.14 - µ)/σ)
= P(Z > (10.14 - 10.2)/0.2)
≈ 0.3085.
Therefore, the probability is approximately 0.3085.
(b) If a sample of 16 is randomly chosen, then the distribution of the sample mean weight is approximately normal with a mean of 10.2 ounces and a standard deviation of σ/√n,
Where n = 16.
The sample standard deviation is given by σ = 0.2, so the standard deviation of the sample mean weight is:
σ/√n = 0.2/√16
= 0.05.
Therefore, the distribution of the sample mean weight is approximately normal with a mean of 10.2 ounces and a standard deviation of 0.05 ounces.
(c) The probability that the sample mean weight of this sample of 16 is less than 10.14 is found using the standard normal distribution as follows:
P(Z < z) = P(Z < (10.14 - µ)/(σ/√n))
= P(Z < (10.14 - 10.2)/(0.2/√16))
≈ P(Z < -1.6)
≈ 0.0548.
Therefore, the probability is approximately 0.0548.
(d) The probability that the sample mean weight of this sample of 16 is greater than 10.14 is found using the standard normal distribution as follows:
P(Z > z) = P(Z > (10.14 - µ)/(σ/√n))
= P(Z > (10.14 - 10.2)/(0.2/√16))
≈ P(Z > -1.6)
≈ 0.9452.
Therefore, the probability is approximately 0.9452.
(e) The probability that the sample mean weight of this sample of 16 is between 10.14 and 10.3 is found
Using the standard normal distribution as follows:
P(a < Z < b) = P((a - µ)/(σ/√n) < Z < (b - µ)/(σ/√n))
= P((10.14 - 10.2)/(0.2/√16) < Z < (10.3 - 10.2)/(0.2/√16))
≈ P(-1.6 < Z < 2)
≈ 0.9452 - 0.0548
= 0.8904.
Therefore, the probability is approximately 0.8904.
(f) Let x be the average weight of a sample of these 16 cheese wedges that is below some value z.
Then, the probability that x is less than z is 0.07.
Using the standard normal distribution, we can find the z-score such that
P(Z < z) = 0.07 as follows:
z = inv Norm(0.07)
≈ -1.4758.
Therefore, the average weight of a sample of these 16 cheese wedges that is below the value z is:
x = µ + z(σ/√n)
= 10.2 + (-1.4758)(0.2/√16)
≈ 10.0625.
Therefore, there is only a 7% chance that the average weight of a sample of these 16 cheese wedges will be below 10.0625.
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Multiple Choice
What is the volume of the pyramid?
A pyramid with height 8 ft and width 7ft.
A. 56 ft³
B.
130 two-thirdsft³
C. 196 ft³
D. 392 ft³
Given f(x)=9+x and g(x)=3x-2, evaluate: fg(x)
Answer:
(f*g)(x) = 3x^2 + 25x - 18
Step-by-step explanation:
(f*g)(x) represents the product of the two functions f and g:
(f*g)(x) = 27x - 18 + 3x^2 - 2x, or, after simplification,
(f*g)(x) = 25x - 18 + 3x^2, or
(f*g)(x) = 3x^2 + 25x - 18
put the cells in the right spot please :(
An insurance company crashed four cars in succession at 5 miles per hour. The cost of repair for each of the four crashes was $421. 5452.5415, $232 Compute the range, sample variance, and sample standard deviation cost of repair, The range is 2-dollars? (Round to the nearest whole number as needed.) (Round to two decimal places as needed)
The range of the repair costs for the four car crashes is $5452.54 - $232 = $5220.54. The sample variance of the repair costs is $4,898,414.69, and the sample standard deviation is $2,214.17.
What are the range, sample variance, and sample standard deviation of the repair costs?The range of the repair costs for the four car crashes is the difference between the highest and lowest cost, resulting in a range of $5220.54. This indicates the variability in the repair costs. The sample variance is a measure of the average squared deviation from the mean, calculated to be $4,898,414.69. It shows the dispersion of the repair costs from the average. The sample standard deviation is the square root of the variance, amounting to $2,214.17. It provides a measure of how spread out the repair costs are, with a higher value indicating greater variability.
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find the missing angle measurement
CORRECT ANSWER GETS BRAINLIEST
The difference between two numbers is 15. Find the two numbers if twice the small number plus three times the large number total 75. (Be sure to use let statments and an equation when solving)
Answer:
21 and 6
Step-by-step explanation:
a will be the larger, b the smaller:
a - b = 15
2b + 3a = 75
First, we'll solve the first equation for a in terms of b:
a = b + 15
Then substitute that in for a in the second equation to get a numerical value for b:
2b + 3(b + 15) = 75
2b + 3b + 45 = 75
5b = 30
b = 6
Next, we'll get a numerical value for a:
a - b = 15
a - 6 = 15
a = 21
Check the math:
2(6) + 3(21) = 12 + 63 = 75
Please lmk if you have questions.
Assume x and y are functions of t.
Evaluate dy/dt for 4xy-3x+4y^3= -76 dx/dt =-8, x=4, and y=-2
The value of dy/dt for the given equation and values is -6.
To evaluate dy/dt, we can differentiate the given equation with respect to t using the chain rule. Starting with the equation 4xy - 3x + 4y^3 = -76, we differentiate both sides with respect to t.
Differentiating each term separately, we get:
(d/dt)(4xy) - (d/dt)(3x) + (d/dt)(4y^3) = 0
Using the chain rule, we can rewrite this as:
4(dy/dt)(x) + 4x(dy/dt) - 3(dx/dt) + 12y^2(dy/dt) = 0
Substituting the given values dx/dt = -8, x = 4, and y = -2, we have:
4(dy/dt)(4) + 4(4)(dy/dt) - 3(-8) + 12(-2)^2(dy/dt) = 0
Simplifying the equation, we get:
16(dy/dt) + 16(dy/dt) + 24 + 48(dy/dt) = 0
80(dy/dt) = -24
(dy/dt) = -24/80
(dy/dt) = -3/10
(dy/dt) = -0.3
Therefore, dy/dt evaluates to -0.3.
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You roll 2 six sided dice. What are the odds of rolling 2 sixes?
A. 1/6
B. 1/36
C. 1/18
D. 1/12
A pizza parlor uses 42 tomatoes for each batch of tomato sauce. About how many batches of sauce can the pizza parlor make from its last shipment of 1,236 tomatoes?
plsssssss help
got 20 mins
the question is: The sin of angle DCB is
Answer:
i. <DCB = [tex]53.13^{o}[/tex]
ii. Sin of <DCB = 0.8
Step-by-step explanation:
Let <DCB be represented by θ, so that;
Sin θ = [tex]\frac{opposite}{hypotenuse}[/tex]
Thus from the given diagram, we have;
Sin θ = [tex]\frac{4}{5}[/tex]
= 0.8
This implies that,
θ = [tex]Sin^{-1}[/tex] 0.8
= 53.1301
θ = [tex]53.13^{o}[/tex]
Therefore, <DCB = [tex]53.13^{o}[/tex].
So that,
Sin of <DCB = Sin [tex]53.13^{o}[/tex]
= 0.8
Sin of <DCB = 0.8
please help find What is AB?
Answer:
oblique
Step-by-step explanation:
Chris makes $25 an hour and is getting a 10% raise. What is her new
earning per hour?
Answer:
$27.50
Step-by-step explanation:
Hope this helps and have a great day!!!!
Step-by-step explanation:
Since his pay is increased by 10 percent, then you multiply 10% by 25 and then add that to 25.
25+10/100(25)=55/2
27.5
Hope that helps :)
Marianna is painting a ramp for the school play in the shape of a right triangular prism. The ramp has dimensions as shown below. She will not paint the back or bottom surfaces of the ramp. What is the surface area of the ramp?
Just include the front and sides of the ramp.
A
4 square inches
B
300 square inches
C
2,905 square inches
D
3,672 square inches
Answer: The correct answer will be 4
Step-by-step explanation:
please help with this ?!?
I’m not sure how to solve this problem
Answer:
a
Step-by-step explanation:
Determine whether the following functions are injective, or surjective, or neither injective nor surjective.
a) f ∶ {a, b, c, d} → {1, 2, 3, 4, 5} given by f (a) = 2, f (b) = 1, f (c) = 3, f (d) = 5. Is f injective? Is f surjective?
b) f ∶ R → R by f (x) = x + 1. Is f injective? Is f surjective?
c) f ∶ Z × Z → Z by f (m, n) = m + n. Is f injective? Is f surjective?
d) f ∶ Z × Z → Z by f (m, n) = m2 + n 2 . Is f injective? Is f surjective?
a) The function f is not injective but is surjective.
b) The function f is injective and surjective.
c) The function f is not injective but is surjective.
d) The function f is not injective and not surjective.
a) The function f maps four elements from the domain {a, b, c, d} to five elements in the codomain {1, 2, 3, 4, 5}. Since there are more elements in the codomain than the domain, f cannot be injective. However, since every element in the codomain is mapped to by at least one element in the domain, f is surjective.
b) The function f(x) = x + 1 is a linear function that maps every real number to a unique real number. Hence, f is injective. Additionally, for every real number y, there exists x = y - 1 such that f(x) = y, meaning f is surjective.
c) The function f(m, n) = m + n maps pairs of integers from the domain Z × Z to integers in the codomain Z. Since there are infinitely many pairs that can result in the same sum, f cannot be injective. However, for every integer in the codomain, there exists at least one pair of integers in the domain whose sum is equal to it, making f surjective.
d) The function f(m, n) = m^2 + n^2 maps pairs of integers from the domain Z × Z to integers in the codomain Z. Since different pairs of integers can have the same sum of squares, f is not injective. Furthermore, there are integers in the codomain that cannot be obtained as a sum of squares, making f not surjective.
In summary, the injectivity and surjectivity of the given functions are as follows: a) not injective, surjective; b) injective, surjective; c) not injective, surjective; d) not injective, not surjective.
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