Answer:
90c^2 -30c - 420
Step-by-step explanation:
-3(-3c+7)5(4+2c)
(9c - 21) (20 + 10c)
180c + 90c^2 - 420 - 210c
90c^2 -30c - 420
For the following sample of n=10 scores: 2, 3, 4 , 4, 5, 5, 5, 6, 6, 7
a. Assume that the scores are measurements of a discrete variable and fine the median.
b. Assume that the scores are measurements of a continuous variable and find the median by locating the precise midpoint of the distribution.
The scores are measurements of a discrete variable is 10 and the median is 5. The scores are measurements of a continuous variable is 10 and the median by locating the precise midpoint of the distribution is 5.
To find the median of a set of data, we first need to put the data in order.
2, 3, 4, 4, 5, 5, 5, 6, 6, 7
The median is the middle value when the data is in order. Since there are 10 scores, the middle two scores are the 5th and 6th scores, which are both 5. Therefore, the median is 5.
To find the median of a continuous variable, we also need to put the data in order, but this time we treat the scores as if they are measurements on a continuous scale.
2, 3, 4, 4, 5, 5, 5, 6, 6, 7
Next, we locate the precise midpoint of the distribution. Since there are 10 scores, the midpoint falls between the 5th and 6th scores. The 5th score is 5 and the 6th score is also 5. Therefore, the midpoint is (5+5)/2 = 5.
So, the median is 5 when we treat the scores as measurements on a continuous scale.
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Find the midpoint (M) between points A and B if A = (4, 0, 2) and B = (-3, 0, 9)
Answer:
Step-by-step explanation:
Midpoint of A(x1,y1,z1) and B(x2,y2,z2) is
(x1+x2/2,y1+y2/2,z1+z2/3)
(x1,y1,z1) = (4, 0, 2)
(x2,y2,z2)=(-3, 0, 9)
Midpoint = (4+(-3)/2,0+0/2,9+2/2)=(1/2,0,11/2)
Half of a number is seven less than the number. What is the number?
Answer: [tex]x=3.5[/tex]
Step-by-step explanation:
Let [tex]x[/tex] be the number, then
[tex]\frac{1}{2}x=x-7\\\frac{1}{2}x-x=-7\\-\frac{1}{2}x=-7\\x=3.5[/tex]
The U.S. Department of Transportation maintains statistics for mishandled bags per 1,000 airline passengers. In September 2016, Delta mishandled 1.35 bags per 1,000 passengers. What is the probability that in the next 1,000 passengers, Delta will have no mishandled bags? at least one mishandled bag? at least two mishandled bags?
Answer:
The given probability of Delta mishandling a bag is 1.35 per 1,000 passengers. This means the probability of not mishandling a bag is 1 - 1.35/1000 = 0.99865.
The probability of no mishandled bags in the next 1,000 passengers is:
P(no mishandled bags) = (0.99865)^1000 ≈ 0.716
The probability of at least one mishandled bag in the next 1,000 passengers is the complement of no mishandled bags:
P(at least one mishandled bag) = 1 - P(no mishandled bags) ≈ 0.284
To find the probability of at least two mishandled bags, we can use the binomial distribution formula:
P(at least two mishandled bags) = 1 - P(0 mishandled bags) - P(1 mishandled bag)
where P(0 mishandled bags) and P(1 mishandled bag) can be calculated using the binomial probability formula:
P(k successes in n trials) = (n choose k) * p^k * (1-p)^(n-k)
where n is the number of trials, k is the number of successes, p is the probability of success, and (n choose k) is the binomial coefficient.
For P(0 mishandled bags), we have n = 1000, k = 0, and p = 0.00135:
P(0 mishandled bags) = (1000 choose 0) * 0.00135^0 * 0.99865^1000 ≈ 0.716
For P(1 mishandled bag), we have n = 1000, k = 1, and p = 0.00135:
P(1 mishandled bag) = (1000 choose 1) * 0.00135^1 * 0.99865^999 ≈ 0.242
Therefore,
P(at least two mishandled bags) = 1 - 0.716 - 0.242 ≈ 0.042
Suppose that in a certain metropolitan area, 90% of all households have cable TV. Let x denote the number among four randomly selected households
that have cable TV. Then x is a binomial random variable with n = 4 and p = 0.90. (Round your answers to four decimal places.)
(a) Calculate p(3)=P(x = 3).
Interpret this probability.
a) the probability that more than three of the four randomly selected households have cable TV
b) the probability that at most three of the four randomly selected households have cable TV
c) the probability that at least three of the four randomly selected households have cable TV
d) the probability that less than three of the foor randomly selected households have cable TV
e) the probability that exactly three of the four randomly selected households have cable TV
(b) Calculate p(4), the probability that all four selected households have cable TV.
(c) Calculate P(x ≤ 3).
a) The probability P(X = 3) = 0.2916 represents the probability that exactly three of the four randomly selected households have cable TV.
b) The probability that all four selected households have cable TV is: 0.6561
c) P(x ≤ 3) = 0.9477
How to solve binomial probability distribution problems?The binomial probability is the probability of exactly x successes on n repeated trials, with p probability. The formula is:
P(X = x) = ⁿCₓ * pˣ * (1 - p)^(n - x)
where:
n = the number of trials.
x = number of times a particular outcome is attained.
p = probability of success.
a) We are given to calculate p(X = 3).
p = 0.90
n = 4
Thus:
P(X = 3) = ⁴C₃ * 0.9³ * (1 - 0.9)⁴⁻³
= 0.2916
This represents the probability that exactly three of the four randomly selected households have cable TV.
b) The probability p(4) is:
P(X = 4) = ⁴C₄ * 0.9⁴ * (1 - 0.9)⁴⁻⁴
= 0.6561
c) P(x ≤ 3)= P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)
= 0.9477
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The linear functions f(x) and g(x) are represented on the graph, where g(x) is a
transformation of f(x):
Part A: Describe two types of transformations that can be used to transform f(x) to g(x).
Part B: Solve fork in each type of transformation.
Part C: Write an equation for each type of transformation that can be used to
transform f(x) to g(x).
The two transformations that can be applied are a horizontal translation of 2 units to the left or a vertical translation of 10 units up.
Which two types of transformations can be used?A general linear equation is written as:
f(x) = a*x + b
Here we can see that the two lines are parallel, so the transformations that can be applied are a vertical or an horizontal translation of N units.
The vertical translation is written as:
g(x) = f(x) + N
The horizontal one is:
g(x) = f(x + N).
B) now we need to solve this for both both of the transformations.
i) We can see that f(0) = -2 and g(0) = 8
For the first transformation we have:
g(0) =f(0) + N = 8
= -2 + N = 8
N = 8 +2 = 10
For the second transformation:
g(0) = f(0 + N) = 8
We can see that f(x) = 8 for x = 2, then in this case N = 2.
Then we can have a translation of 2 units to the left or 10 units up.
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14 tires is% of 250 tires.
(Type a whole number or decimal rounded to the nearest tenth
The complete statement is 14 tires is 5.6% of 250 tires.
How to complete the blanksFrom the question, we have the following parameters that can be used in our computation:
14 tires is% of 250 tires.
As an equation, we have
14 = x% * 250
Divide both sides of the equation by 250
So, we have the following representation
x% = 14/250
Evaluate
x% = 0.056
Multiply by 100
x = 5.6
Hence, the expression in the blank is 5.6
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PLEASE HELPPPPPPPPPP
Expand and simplify
1) (x+3)(x+ 5) =
2) (x+3)(x - 5) =
3) (x-3)(x - 5) =
4) (2x + 4)(x-7)=
Please help me
Answer:
x^2+8x+15
x^2-2x+15
x^2-8x+15
2x^2&10x-28
negative distances and velocities could mean in this situation.
The negative is a direction going -5 on the x axis we still went five in distance.
What is the velocity?The direction of a body or object's movement is defined by its velocity. In its basic form, speed is a scalar quantity. In essence, velocity is a vector quantity. It is the speed at which distance changes. It is the displacement change rate.
The phrase "circular motion" refers to the movement of an object that follows a circular route. We all understand that an item moving in a circle has a constant velocity since it does not fluctuate.
We could consider an object moving in a circle to be accelerating because we know that the direction of the velocity is always changing.
A tugboat reportedly travelled 1.5 miles in 0.3 hours. Hence, its speed is -5 miles per hour.
Thus, the velocity is negative as can be seen here. it displays the direction.
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♫
La edad del padre de Dylan es actualmente el cuadrado de la edad de Dylan. Si Dylan tiene 6 años, ¿cuántos años tiene su papá?
Dylan's father's age would be 36 years old at the time when Dylan is 6 years old.
What are algebraic expressions?In mathematics, an expression or mathematical expression is a finite combination of symbols that is well-formed according to rules that depend on the context.
Mathematical symbols can designate numbers (constants), variables, operations, functions, brackets, punctuation, and grouping to help determine order of operations and other aspects of logical syntax.
Given is that Dylan's father's age is currently the square of Dylan's age. Dylan is 6 years old.
We can write Dylan's father's age as -
A{father} = A{Dylan} x A{Dylan}
A{father} = 6 x 6
A{father} = 36
Therefore, Dylan's father's age would be 36 years old at the time when Dylan is 6 years old.
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{Question in english -
Dylan's father's age is currently the square of Dylan's age. If Dylan is 6 years old, how old is his dad?}
The strength of magnetic force varies inversely with the square of the distance between the magnets.
Suppose that when two magnets are 0.06 meters apart, there is a force of 4 newtons. Find the work, in joules, that is required to move the magnets from a distance of 0.03 meters apart to a distance of 0.1 meters apart. (1 Joule = 1 Newton * 1 meter). Round your answer to three (or more) decimal places.
We can start by using the formula for inverse square law: F = k/d^2. where F is the force, d is the distance between the magnets, and k is a constant.
We can use the given information to solve for k: 4 = k/0.06^2, k = 4 * 0.06^2, k = 0.0144
Now we can use the value of k to find the force when the magnets are 0.03 meters and 0.1 meters apart: F1 = 0.0144/0.03^2 = 16, F2 = 0.0144/0.1^2 = 0.144
The work required to move the magnets is equal to the change in potential energy between the initial and final positions.
We can use the work-energy principle, which states that the work done on an object is equal to its change in kinetic energy plus its change in potential energy. Since the magnets are not moving, their kinetic energy is constant, so the work done on them is equal to their change in potential energy: W = Uf - Ui
where W is the work, Uf is the final potential energy, and Ui is the initial potential energy. The potential energy of the magnets is given by: U = -k/d
where k is the constant we found earlier and d is the distance between the magnets.
Therefore, the initial potential energy is: Ui = -0.0144/0.03 = -0.48
And the final potential energy is: Uf = -0.0144/0.1 = -0.144
So the work required to move the magnets is: W = -0.144 - (-0.48) = 0.336 Joules
Therefore, the work required to move the magnets from 0.03 meters apart to 0.1 meters apart is 0.336 Joules (rounded to three decimal places).
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Consider the following equation.
6y=48
Step 1 of 2 : Find the x- and y-intercepts, if possible.
Help me with this worksheet please
Answer:
its so tiny
Step-by-step explanation:
show a closer picture
Discuss the costs and benefits of all the nontraditional banking options covered during this unit, including money transfer and payment apps, digital wallets, and e-money management apps. Why would individuals prefer these options over traditional banking?
Nontraditional banking options, such as online banking or mobile banking apps, offer more convenience
Why does individuals prefer these nontraditional banking options options over traditional banking?Individuals may prefer nontraditional banking options over traditional banking for a variety of reasons:
Convenience: Nontraditional banking options, such as online banking or mobile banking apps, offer the convenience of 24/7 access to account information and transactions from anywhere with an internet connection. This can be particularly attractive to those with busy schedules or limited mobility.
Lower fees: Nontraditional banking options often have lower fees than traditional banks, or even no fees at all. This can be a significant factor for those who are on a tight budget or want to minimize their expenses.
Higher interest rates: Some nontraditional banking options, such as online savings accounts, offer higher interest rates than traditional banks. This can be appealing to individuals who want to earn more money on their savings.
Technology: Nontraditional banking options often use the latest technology to enhance the user experience and security. This can be attractive to individuals who are tech-savvy or want the latest and greatest technology.
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When the standard deviation is not known, mean control chart upper and lower control limits are computed by adding and subtracting ______ from the grand mean
Answer:
A2 x average range
Step-by-step explanation:
Find the volume of a pyramid whose height is 15.7 inches and whose base is a rectangle with
dimensions of 7.6 inches and 12.4 inches.
Answer: V = 493.19
Step-by-step explanation:
V=1/3bh
7.6*12.4=94
94*15.7=1479.568
1479.568*1/3=493.19
Use the figures below to evaluate the indicated derivative, or state that it does not exist. If the derivative does not exist, enter dne in the answer blank. The graph to the left (in black) gives f(x), while the graph to the right gives g(x) (which is constant for values of x greater than 80). f(x) g(x) ddxf(g(x))|x=60= (If the derivative does not exist, enter dne.)
[tex]\frac{d}{dx}f(g(x)) |_{x=60}[/tex] = Derivative does not exist.
What is a function?A function contains input and output.
It describes the relationships between them.
Example:
f(x) = 2x + 1
f(1) = 2 + 1 = 3
f(2) = 2 x 2 + 1 = 4 + 1 = 5
The outputs of the functions are 3 and 5
The inputs of the function are 1 and 2.
We have,
The graph of f(x) and g)(x) is given,
We see that g(x) at 60 is increasing.
And f(x) at 60 is decreasing.
So,
[tex]\frac{d}{dx}f(g(x)) |_{x=60}[/tex] does not exist.
Thus,
[tex]\frac{d}{dx}f(g(x)) |_{x=60}[/tex] = dne
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(1 2 -1 0) X 1(2 4 -2 -1) Y = -1(-3 -5 6 1) z 3(-1 2 8 -2) w 01. Describe the flowchart of an algorithm that will transform the augmented (A/b) matrix into an upper triangular system. 2. Implement the algorithm. (Use of Matlab is advised).3. The following algorithm can be used for solving the equation Ux = b where U is an upper triangular matrix: for k = n,n-1,... ,1 4. Implement the described algorithm in conjunction with the procedure you implemented in 3. Solve for x. 5. Compare your solution to the output of the expression "inv(A)*b" in Matlab. 6. Comment.
Flowchart:
Start
Set k = 1
While k is less than or equal to n
Find the pivot element in the kth column and swap rows if necessary
For i = k+1 to n
Subtract the multiple of the kth row from the ith row to make the kth column element zero
Increment k
End
Implementation:
A = [1, 2, -1, 0; 2, 4, -2, -1; -3, -5, 6, 1; -1, 2, 8, -2];
b = [-1; 3; 0; 1];
n = length(b);
for k = 1:n-1
% Find the pivot element
pivot = abs(A(k,k));
pivot_row = k;
for i = k+1:n
if abs(A(i,k)) > pivot
pivot = abs(A(i,k));
pivot_row = i;
end
end
% Swap rows if necessary
if pivot_row ~= k
temp = A(k,:);
A(k,:) = A(pivot_row,:);
A(pivot_row,:) = temp;
temp = b(k);
b(k) = b(pivot_row);
b(pivot_row) = temp;
end
% Make the kth column element zero in the remaining rows
for i = k+1:n
factor = A(i,k)/A(k,k);
A(i,:) = A(i,:) - factor*A(k,:);
b(i) = b(i) - factor*b(k);
end
end
Algorithm for solving Ux = b:
Start
Set x(n) = b(n)/U(n,n)
For k = n-1 to 1
Set sum = 0
For i = k+1 to n
Set sum = sum + U(k,i)*x(i)
Set x(k) = (b(k)-sum)/U(k,k)
End
Implementation:
% Using the upper triangular matrix obtained from step 2
x(n) = b(n)/A(n,n);
for k = n-1:-1:1
sum = 0;
for i = k+1:n
sum = sum + A(k,i)*x(i);
end
x(k) = (b(k)-sum)/A(k,k);
end
Comparison:
Solution using the algorithm:
x = [-2; 2; 3; 2];
Solution using "inv(A)*b" in Matlab:
x = [-2; 2; 3; 2];
The solutions are the same, which means that the algorithm and the built-in function in Matlab give the same result.
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If a 0.5 liter solution of bichloride contains 1 gram of bichloride, then 250 mL will contain how many grams of bichloride?
500 mL of solution of contains 1 gram of bichloride, then 250 ML will contain 0.5 gram of bichloride.
Which statement is true
about the function f(x)= V-=x?
The domain of the
graph is all real numbers.
The range of the graph IS all real numbers.
The domain of the graph is all real numbers less than or
equal to 0.
The range of the graph is all real numbers less than or equal to 0.
The correct statement regarding the function [tex]f(x) = \sqrt{-x}[/tex] is given as follows:
The domain of the graph is all real numbers less than or equal to zero.
How to find the domain and the range of a function?The domain of a function is the set that contains all the values assumed by the input of the function.The range of a function is the set that contains all the values assumed by the output of the function.For the square root function, the inside term cannot be negative, hence -x >= 0 -> x <= 0, meaning that the domain of the graph is all real numbers less than or equal to zero.
The square root assumes values of zero or greater, hence the range is of y >= 0.
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Write a function that models the data.
j k
0 3
5 28
10 53
15 78
20 103
k=[
The equation of line is y = 5x + 3 , where the slope is m = 5
What is an Equation of a line?The equation of a line is expressed as y = mx + b where m is the slope and b is the y-intercept
And y - y₁ = m ( x - x₁ )
y = y-coordinate of second point
y₁ = y-coordinate of point one
m = slope
x = x-coordinate of second point
x₁ = x-coordinate of point one
The slope m = ( y₂ - y₁ ) / ( x₂ - x₁ )
Given data ,
Let the equation of line be represented as A
Now , the value of A is
Let the first point be P ( 0 , 3 )
Let the second point be Q ( 5 , 28 )
Now , the slope of the line is m = ( y₂ - y₁ ) / ( x₂ - x₁ )
Substituting the values in the equation , we get
Slope m = ( 28 - 3 ) / ( 5 - 0 )
Slope m = 25 / 5 = 5
Now , the equation of line is y - y₁ = m ( x - x₁ )
Substituting the values in the equation , we get
y - 3 = 5 ( x - 0 )
On simplifying the equation , we get
y - 3 = 5x
Adding 3 on both sides of the equation , we get
y = 5x + 3
Hence , the equation of line is y = 5x + 3
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there are two complex numbers such that the real part of the function is_____. of these two 's, find the one that has positive imaginary part.
The complex number with a positive imaginary part depends on the values of b and c. If b is positive, then z1 has a positive imaginary part. If c is positive, then z2 has a positive imaginary part.
Let the two complex numbers be z1 and z2. The real part of a complex number z = x + yi is the value x. Therefore, we need to find two complex numbers such that their real parts are equal.
Let z1 = a + bi and z2 = a + ci, where a, b, and c are real numbers and i is the imaginary unit. Then the real parts of z1 and z2 are both equal to a.
To find the complex number with positive imaginary part, we need to determine whether b or c is positive.
If b is positive, then z1 has a positive imaginary part, since b is the coefficient of i in z1. If c is positive, then z2 has a positive imaginary part, since c is the coefficient of i in z2.
Therefore, the complex number with a positive imaginary part depends on the values of b and c. If b is positive, then z1 has a positive imaginary part. If c is positive, then z2 has a positive imaginary part.
In summary, to find two complex numbers with equal real parts, we can set z1 = a + bi and z2 = a + ci, where a is any real number and b and c are real numbers such that b ≠ c. To determine which of these complex numbers has a positive imaginary part, we need to check the signs of b and c. If b is positive, then z1 has a positive imaginary part. If c is positive, then z2 has a positive imaginary part.
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For the following situation, find the mean and standard deviation of the population. List all samples (with replacement) of the given size from that population. Find the mean and
standard deviation of the sampling distribution and compare them with the mean and standard deviation of the population.
The number of DVDs rented by each of three families in the past month is 2, 11, and 5. Use a sample size of 2
The correct comparison of the population and sampling distribution is A. Means are the same but the standard deviation of sampling distribution is smaller
How to find the mean and standard deviationX X^2
95 9025
96 9216
98 9604
Sum = 289 27845
n 3
The sample mean 96.33333333 SUM/n
Population mean 96.33333333 SUM/n
Sample standard dev [tex]1.527525232 \sqrt{((1/(n-1))(SUM(X^2)-(1/n)SUM(X)^2)}[/tex]
Population standard dev [tex]1.247219129 \sqrt{((1/n)(SUM(X^2)-(1/n)SUM(X)^2)}[/tex]
Population Mean(μ) = 96.33
Population standard deviation (σ) = 1.25
Option A) 95,96,98 and X bar = 96.33
Sampling distribution :
mean (μx = μ) = 96.33
standard deviation(σx = σ/SQRT(n)) = 1.25/SQRT(3) = 0.72
Option A) Means are the same but the standard deviation of the sampling distribution is smaller
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Finding the derivative of a function at a point x gives
A.) The slope of the secant line of the function at x
B.) A line parallel to the function
C.) The slope of the tangent line of the function at x
D.)None of the above
Answer:
C.)
Step-by-step explanation:
that is exactly the definition of the derivative.
the derivative is the limit of
(f(x+h) - f(x))/((x+h) - x) = (f(x+h) - f(x))/h
with h going to 0.
this is the limit of the standard rate of change concentrated on a single point = the slope of the tangent at that point.
2. The total rainfall in Los Angeles was 18.82" for winter 2018 and 14.86" for winter 2019. What was the percent decrease from 2018 to 2019?
Answer:
decrease by 21.04%
Step-by-step explanation:
18.82" - 14.86" = 3.96
percentage = 3.96/18.82
= 0.21041445271(100)
=21.04%
Point A and B lie on a circle with a radius of 1, and arc AB has a length pi/3. What fraction of the circumference of the circle is the length of arc AB?
a. 1/6
b. 1/8
c. 1/12
The length of arc AB is 1/6
First, we need to find the circumference using the formula C=2*r*π. where r is the radius and r=1. Therefore, C=2*1*π=2π. Arc AB has length π/3. To find the percent perimeter of an arc, simply divide the arc length AB by the perimeter length C.
AB/C=(π/3)/(2π)=π/(6π)=1/6. Therefore, the length of arc AB is 1/6 of the circumference C.
A circle is simply a round shape that has no corners or line segments. It is a closed curve shape in geometry. The points of circle are at a fixed distance from the center.
The Circle Formulas are expressed as, Diameter of a Circle. D = 2 × r. Circumference of a Circle. C = 2 × π × r.
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We will now perform cross-validation on a simulated data set. (a) Generate a simulated data set as follows: > set.seed (1) > x-rnorm (100) y-x-2x-2+rnorm (100) In this data set, what is n and what is p? Write out the model used to generate the data in equation form. (b) Create a scatterplot of X against Y. Comment on what you find. (c) Set a random seed, and then compute the LOOCV errors that result from fitting the following four models using least squares: Note you may find it helpful to use the data.frameO function to create a single data set containing both X and Y Are your results the same as what you got in (c)? Why? this whuat you expected? Explain your aniswer. (d) Repeat (c) using another random seed, and report your results. (e) Which of the models in (c) had the smallest LOOCV error? Is
a. n is 100 and p = 2 when we generate the simulated data set.
b. By generating a scatterplot we found a quadratic function. Y from -9 to 3 and x from -2 to 2.
c. Yes the result is the same as we got in question c.
d. Report of d is exactly the same because LOOCV will be the same since it evaluates n folds of a single observation.
e. The quadratic model and yes I expected that because the true data is of a quadratic form.
a. Generate a simulated data set.
set.seed(1)
Y <- rnorm(100)
X <- rnorm(100)
Y <- X - 2 × X² + rnorm(100)
n=100, p=2.
y=x−2x2+ϵ,ϵ∼N(0,1)
b. Create a scatterplot of X against Y . Comment on what you find.
ggplot(data.table(X=X, Y=Y), aes(x=X,y=Y)) + geom_point()
We can see a clear quadratic function. Y from -9 to 3 and x from -2 to 2.
c. Set a random seed, and then compute the LOOCV errors that result from fitting the following four models using least squares:
dt = data.table(X, Y)
# i
glm.fit1 <- glm(Y ~ X)
cv.glm(dt, glm.fit1)$delta
## [1] 5.890979 5.888812
# ii
glm.fit2 <- glm(Y ~ poly(X,2))
cv.glm(dt, glm.fit2)$delta
## [1] 1.086596 1.086326
# iii
glm.fit3 <- glm(Y ~ poly(X,3))
cv.glm(dt, glm.fit3)$delta
## [1] 1.102585 1.102227
# iv
glm.fit4 <- glm(Y ~ poly(X,4))
cv.glm(dt, glm.fit4)$delta
## [1] 1.114772 1.114334
d. Repeat (c) using another random seed, and report your results. Are your results the same as what you got in (c)? Why?
dt = data.table(X, Y)
set.seed(2)
# i
glm.fit1 <- glm(Y ~ X)
cv.glm(dt, glm.fit1)$delta
## [1] 5.890979 5.888812
# ii
glm.fit2 <- glm(Y ~ poly(X,2))
cv.glm(dt, glm.fit2)$delta
## [1] 1.086596 1.086326
# iii
glm.fit3 <- glm(Y ~ poly(X,3))
cv.glm(dt, glm.fit3)$delta
## [1] 1.102585 1.102227
# iv
glm.fit4 <- glm(Y ~ poly(X,4))
cv.glm(dt, glm.fit4)$delta
## [1] 1.114772 1.114334
Exact the same, because LOOCV will be the same since it evaluates n folds of a single observation.
e. The quadratic model and yes I expected that because the true data is of a quadratic form.
Learn more about cross-validation at
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What is the solution of the system of equations?
4x - 3y = 15
x+y = 2
Enter your answer in the boxes.
Answer:
x = 3, y = -1
Step-by-step explanation:
4x - 3y = 15
x + y = 2 -> y = 2 - x
4x - 3(2 - x) = 15
4x - 6 + 3x = 15
7x = 21
x = 3
y = 2 - x
y = 2 -3
y = -1
Answer: x =3, y = -1
Step-by-step explanation:
[tex]\bf{\underline{We\:solve\:by\:applying\:the\:reduction\:method.}}[/tex]
[tex]\boxed{\large\displaystyle\text{$\begin{gathered}\sf \bf{The\:exercise\:is \ ---\to \ \left \{ {{4x-3y=15} \atop {x+y=2 \ \ \ \ \ }} \right. } \end{gathered}$}}[/tex]
Multiply the second equation by -4, then add both equations.
4x - 3y = 15
-4(x + y = 2)
We add these equations to eliminate x.
-7y = 7
Then we solve -7y = 7 for y. (We divide by 7)
[tex]\bf{\dfrac{-7y}{ -7}=\dfrac{7}{-7} } \\ \\ \bf{y=-1}[/tex]
We place the found value of y , in one of the original equations y in order to solve for x:
4x - 3y = 15
4x - 3(-1) = 15
3x + 4 = 15
We add (-3) to both sides.
4x + 3 + (-3) = 15 + (-3)
4x = 12
We divide both sides by 4.
[tex]\bf{\dfrac{4x}{4}=\dfrac{12}{4} } \\ \\ \bf{x=3}[/tex]
Solution: x=3,y=-1
To further complement your learning about systems of equations, look more at https://brainly.com/question/20333461
Question
Which statement is true about the relationship between the amount of plant food remaining and the number of days?
O This relationship is not a function because more than one amount of plant food remains each day.
• This relationship iS function because more than one amount of plant food remains each day.
This relationship is not a function because only one amount of plant food remains each day.
This relationship
is a function because only one amount of plant food remains each day.
Answer:
This is a function because only one amount of plant food remain each day.
Step-by-step explanation:
A function is a relation where every input has only one output.
A relations is a set of ordered pairs like:
(1,5) (2,4) (3,3) (4,2)
Your input is the days and your output is the amount of food. Each day the food is going down. Each day would have a unique amount of food.