Answer:
Step-by-step explanation:
To prove that [tex]w_1,\dots w_n[/tex] form a basis for W, we must check that this set is a set of linearly independent vector and it generates the whole space W. We are given that T is an isomorphism. That is, T is injective and surjective. A linear transformation is injective if and only if it maps the zero of the domain vector space to the codomain's zero and that is the only vector that is mapped to 0. Also, a linear transformation is surjective if for every vector w in W there exists v in V such that T(v) =w
Recall that the set [tex]w_1,\dots w_n[/tex] is linearly independent if and only if the equation
[tex]\lambda_1w_1+\dots \lambda_n w_n=0[/tex] implies that
[tex]\lambda_1 = \cdots = \lambda_n[/tex].
Recall that [tex]w_i = T(v_i)[/tex] for i=1,...,n. Consider [tex]T^{-1}[/tex] to be the inverse transformation of T. Consider the equation
[tex]\lambda_1w_1+\dots \lambda_n w_n=0[/tex]
If we apply [tex]T^{-1}[/tex] to this equation, then, we get
[tex] T^{-1}(\lambda_1w_1+\dots \lambda_n w_n) =T^{-1}(0) = 0[/tex]
Since T is linear, its inverse is also linear, hence
[tex]T^{-1}(\lambda_1w_1+\dots \lambda_n w_n) = \lambda_1T^{-1}(w_1)+\dots + \lambda_nT^{-1}(w_n)=0[/tex]
which is equivalent to the equation
[tex]\lambda_1v_1+\dots + \lambda_nv_n =0[/tex]
Since [tex]v_1,\dots,v_n[/tex] are linearly independt, this implies that [tex]\lambda_1=\dots \lambda_n =0[/tex], so the set [tex]\{w_1, \dots, w_n\}[/tex] is linearly independent.
Now, we will prove that this set generates W. To do so, let w be a vector in W. We must prove that there exist [tex]a_1, \dots a_n[/tex] such that
[tex] w = a_1w_1+\dots+a_nw_n[/tex]
Since T is surjective, there exists a vector v in V such that T(v) = w. Since [tex]v_1,\dots, v_n[/tex] is a basis of v, there exist [tex]a_1,\dots a_n[/tex], such that
[tex]a_1v_1+\dots a_nv_n=v[/tex]
Then, applying T on both sides, we have that
[tex]T(a_1v_1+\dots a_nv_n)=a_1T(v_1)+\dots a_n T(v_n) = a_1w_1+\dots a_n w_n= T(v) =w[/tex]
which proves that [tex]w_1,\dots w_n[/tex] generate the whole space W. Hence, the set [tex]\{w_1, \dots, w_n\}[/tex] is a basis of W.
Consider the linear transformation [tex]T:\mathbb{R}^2\to \mathbb{R}^2[/tex], given by T(x,y) = T(x,0). This transformations fails to be injective, since T(1,2) = T(1,3) = (1,0). Consider the base of [tex]\mathbb{R}^2[/tex] given by (1,0), (0,1). We have that T(1,0) = (1,0), T(0,1) = (0,0). This set is not linearly independent, and hence cannot be a base of [tex]\mathbb{R}^2[/tex]
A random sample of 18 adults, chosen from the 1500 adults in the town, took a survey asking their opinion on a recent property tax change. 25% of those who responded said they were in favor of the change. The company running the survey wants to construct a confidence interval estimating the proportion of all adults in the town who support the change. Which of the conditions for inference have been satisfied?
I. Random condition
II. Normal condition
III. 10% condition
A) I
B) II
C) I and III
D) II and III
E) I, II, and III
Answer:
C) I & III
Step-by-step explanation:
Given:
Sample size, n = 18
Sample proportion = 25% = 0.25
Here, a random sample of 18 adults were chosen from the 1500 adults in town. This shows that the random condition was satisfied because the sample was drawn randomly from the general population of adults in the town.
For the normal condition to be satisfied, np should be greater than 10, ie np > 10.
In this case, np = 18 * 0.25 = 4.5
Since np is less than 10, the normal condition was not satisfied.
For the 10% condition to be satisfied, sample size should not be more than 10% of the general population.
Here, the sample size is 18 and the population is 1500. Therefore,
[tex] \frac{18}{1500} * 100 = 1.2 [/tex]
Since the sample size is 1.2% of the population which is less than 10%, the 10% condition was satisfied.
The correct option is C, because only I & III were satisfied.
I run a book club with $n$ people, not including myself. Every day, for $365$ days, I invite four members in the club to review a book. What is the smallest positive integer $n$ so that I can avoid ever having the exact same group of four members over all $365$ days?
Answer: 12
Step-by-step explanation:
If we have n people and we want to do groups of 4, the total number of different combinations is:
[tex]c = \frac{n!}{(n - 4)!4!}[/tex]
and we want find the smallest n such c > 365.
let's do it by brute force:
if n = 5, we have:
[tex]c = \frac{5!}{1!*4!} = 5[/tex]
if n = 6
[tex]c = \frac{6!}{2!*4!} = \frac{6*5}{2} = 15[/tex]
if n = 7
[tex]c = \frac{71}{3!*4!} = \frac{7*6*5}{3*2} = 35[/tex]
if n = 8
[tex]c = \frac{8!}{(4!*4!} = \frac{8*7*6*5}{4*3*2} = 70[/tex]
if n = 9
[tex]c = \frac{9!}{5!*4!} = \frac{9*8*7*6*5}{5*4*3*2} = 126[/tex]
if n = 10
[tex]c = \frac{10!}{6!*4!} = \frac{10*9*8*7}{4*3*2} = 210[/tex]
So you can see the patern here.
So we have the previous number multiplied by n and divided by n - 4
if n = 11
C = 210*11/(11- 4) = 330
if n = 12
C = 330*12/(12 - 4) = 495
Then the minimum number of members such we have more than 365 combinations is 12 members
A triangle xyz has vertices
X (6,4), Y (5,-3) and (5,-1).
Find
whether
it's a
scalene triangle
Answer:
yes scalene as xy=7cm
xz=5cm
yz=2cm
Step-by-step explanation:
by the graph
hope this helps plzz mark me brainliest
Answer:
Scalene
Step-by-step explanation:
Let's find XY, XZ and YZ
XY = √[(6-5)^2 + (4-(-3)] = √[(1^2 ) + (7^2)]=√(1+49) =√50 = 7.0711
YZ = √[(5-5)^2 + (-3 -(-1))^2 ]=√[(0^2) + (-2)^2] =√(0 + 4) = 2
XZ = √[(6-5)^2 + (4-(-1)^2] = √[(1^2 ) + (5^2)]=√(1+25) =√26 = 5.099
By observation XY , XY and YZ are not the same; hence none of the sides is equal
A scalene triangle has no side equal
**10 POINTS PLEASE HELP**
Can each of the shapes below be expressed as a composite figure of equilateral triangles? Select Yes or No for each shape.
A pyramid
(select)
A hexagon
(select)
A pentagon
(select)
Answer:
A pyramid yes
a hexagon no
a pentagon no
Step-by-step explanation:
The sum of the speeds of two trains is
726.1 miles per hour. If the speed of the first train is
9.9 mph faster than that of the second train, find the speeds of each.
Answer:
Train 1: 368 mph
Train 2: 358.1 mph
Step-by-step explanation:
We can write 2 equations to represent this problem.
[tex]x+y=726.1[/tex]
[tex]x=9.9+y[/tex]
The x represents the first train and the y represents the second train.
We can plug in x into the first equation.
[tex](9.9+y)+y=726.1[/tex]
[tex]9.9+2y=726.1[/tex]
[tex]2y=716.2[/tex]
[tex]y=358.1[/tex]
Now that we know our y, we can find our x.
[tex]x=9.9+y[/tex]
[tex]x=9.9+358.1[/tex]
[tex]x=368[/tex]
How many proportional relationships are shown in the coordinate plane here???
Answer:
3
Step-by-step explanation:
In the graph, there are three lines , so that indicates that there are 3 proportional relationships
The average human gestation time is 266 days from conception. A researcher suspects that proper nutrition plays an important role and that low-income women with inadequate food intake would have shorter gestation times even when given vitamin supplements. A random sample of 20 low-income women who were given vitamin supplement throughout their pregnancy had a gestation time from conception of x - 256 days The researcher's alternative hypothesis for the test is:______.
a. Ha : μ =/ 256.
b. Ha: μ = 266.
c. Ha : μ < 266.
d. Ha : μ < 256.
Answer:
c. Ha : μ < 266.
Step-by-step explanation:
Null hypothesis: The mean value is x.
Alternate hypothesis. The mean value is different than x, greater than x, smaller than x...
In this question:
Average of 266 days, so the null hypothesis is that the mean is 266.
In the sample:
He suspects that the generation time is less than 266. So
c. Ha : μ < 266.
A mixture of 5 pounds of fertilizer A, 13 pounds of fertilizer B, and 4 pounds of fertilizer C provides the optimal nutrients for a plant. Commercial brand X contains equal parts of fertilizer B and fertilizer C. Commercial brand Y contains one part of fertilizer A and two parts of fertilizer B. Commercial brand Z contains two parts of fertilizer A, five parts of fertilizer B, and two parts of fertilizer C. How much of each fertilizer brand is needed to obtain the desired mixture? (If the system is dependent enter a for brand X and enter brand Y and brand Z in terms of a.)
Answer:
x = 2; y = 3; z = 1
Step-by-step explanation:
For the first fertilizer (A) we can form the equation:
y + 2z = 5
For the second fertilizer (B) we can form the equation:
x + 2y + 5z = 13
For the third fertilizer (C) we can form the equation:
x + 2z = 4
solving simulteneously:
y = 5 - 2z
x = 4 -2z
Substituting (i) and (ii) into (2)
4 - 2z + 10 -4z + 5z = 13
14-z =13, therefore z = 1
substituting z into (i) and (ii)
y = 3
x = 2
HELP MEE ILL MARK BRAINLEIST
Answer:
3x-3 I think that's it.
Step-by-step explanation:
Answer:
The vertex is (1, -4)
Step-by-step explanation:
Choose the correct correspondence. U ∠T ∠S ∠R
Answer:
angle S
Step-by-step explanation:
You have to make the triangles congruent. Therefore, you have to flip one triangle vertically and horizontally. (To see the picture google choose the correct correspondence, I am looking at the one with two triangles in the figure.) If you imagine putting them over top of each other, then U goes over S.
Sorry my answer was so late.
Answer:
The answer is going to be S
Step-by-step explanation:
Which function is a quadratic function
FIRST PERSON TO ANSWER WILL BE MARKED BRAINLEST
Jessica always uses the same ratio of green beads to blue beads when she makes necklaces. The graph shows these equivalent ratios. Which table shows the same data?
Answer:
Its B
stuff:
ITS BBBBBBBBBBBBBBBBBBBB
Answer:
B
Step-by-step explanation:
Trust me on this, also can I have brainiest please?
Hope you do well! :D
760-__=214=225+231need help
Hey, actually I am new here, otherwise I was on brainly.in (India)....so can anyone tell me about some moderators here.....need help....
Solve both equations the lines are absolute value and please include detailed steps for each
I’ll report you if you don’t put a legit answer.
Answer:
see below
Step-by-step explanation:
|x+8| ≤ 4
Separate into two equations one positive and one negative , remembering to flip the inequality for the negative
x+8 ≤ 4 x+8 ≥ -4
Subtract 8 from each side
x+8 -8 ≤ 4-8 and x+8-8 ≥ -4-8
x ≤-4 and x ≥ -12
Writing as one function
-12 ≤x ≤-4
|x-8|+5 ≥ 11
Subtract 5 from each side
|x-8|+5-5 ≥ 11-5
|x-8| ≥ 6
Separate into two equations one positive and one negative , remembering to flip the inequality for the negative
x-8 ≥ 6 or x-8 ≤ -6
Add 8 to each side
x-8+8 ≥ 6+8 or x-8+8 ≤ -6+8
x ≥ 14 or x ≤ -2
Answers and Step-by-step explanations:
9. | x + 8 | ≤ 4
Remember that absolute value just denotes the distance between the argument within the absolute value signs and 0 on a number line. That means that if the item within the absolute value is negative, the absolute value of it will be the positive value because distance is always positive.
That means we have 2 cases here: x + 8 > 0 (positive) or x + 8 < 0 (negative).
Case 1: x + 8 > 0
x + 8 ≤ 4
x ≤ -4
Case 2: x + 8 < 0
-(x + 8) ≤ 4
-x - 8 ≤ 4
-x ≤ 12
x ≥ -12
Combining these two inequalities, we get:
-12 ≤ x ≤ -4
10. | x - 8 | + 5 ≥ 11
Let's isolate the absolute value expression by subtracting 5 from both sides: | x - 8 | ≥ 6
We again have two cases: x - 8 > 0 and x - 8 < 0.
Case 1: x - 8 > 0
x - 8 ≥ 6
x ≥ 14
Case 2: x - 8 < 0
-(x - 8) ≥ 6
-x + 8 ≥ 6
-x ≥ -2
x ≤ 2
Combining these two inequalities, we get:
x ≤ 2 and x ≥ 14
There are 4 boy in a class of 13 students? What is the ratio of girls to boys?
Answer:
4:9
Step-by-step explanation:
13-4=9 AND THERES 4 boys so that means there are 9 girls. So 4:9
What’s the correct answer for this?
Answer:
The first option
Step-by-step explanation:
In the image, we can notice that NQ is longer than PQ, similar to how JH is longer than NJ. Thus, NQ must be aligned with JH and PQ with JN. As PN and HN are clearly the longest for each triangle, those must be aligned as well.
All of the responses have NP and NH aligned.
The last response does not have NQ aligned with JH.
The second and third do not align PQ and JN.
The first option is our answer.
Write an expression for this problem Mr. Thomas Brings $100 to a fundraiser he wants to leave the event with at least $50 in his pocket guests at the fundriaser buy raffle tickets for several different prizes. each raffle ticket, t, costs $2.50. how many raffle tickets can mr thomas buy and still leave with at least 50 dollars in his pocket. DO NOT SOLVE. i only want the expression
Answer:
Step-by-step explanation:
Well Mr.Thomas has 50 dollars to spend so if you divide 2.50 from 50 you will get 20 so he can get 20 raffle tickets and still walk out with another 50 in his pocket.
In snapdragons, variation in flower colori determined by a single gene (Hartl and Jones 2005). RR individuals are red, Rr (heterozy- gous) individuals are pink, and rr individuals are white. In a cross between heterozygous individuals, the expected ratio of red- flowered:pink-flowered:white-flowered off- spring is 1:2:1.
a. The results of such a cross were 10 red-, 21 pink-, and 9 white-flowered offspring. Do these results differ significantly (at a 5% level) from the expected frequencies?
b. In another, larger experiment, you count 100 times as many flowers as in the experiment in part (a) and get 1000 red, 2100 pink, and 900 white. Do these results differ significantly from the expected 1:2:1 ratio?
c. Do the proportions observed in the two experiments [i.e., in parts (a) and (b)] differ? Did the results of the two hypothesis tests differ? Why or why not?
Find the given attachments
Pls help me 15 points if you fake it u get reported
Answer:
The volume question is 1,120 I think
Julie went to the store with $20.00. if she bought 8 cans of dog food for $.67 per can, how much money did she have left? IF YOU ANSWER THIS QUESTION, I WILL RATE YOUR ANSWER 5 STARS, BRAINLIEST ANSWER, AND A THANK YOU!
PLEASE ANSWER THIS QUESTION ASAP!
Answer:
$14.64
Multiply 8 by .67 which is 5.36
Subtract 5.36 from 20.00 and that's 14.64
Answer:
14.64
Step-by-step explanation:
Have a wonderful day hope this helps
If a = 5 units , b = 8 C = 4 Units, and d = 3 units what is the volume of the composite figure?
Answer:
[tex]V = 208\,u^{3}[/tex] (Option C)
Step-by-step explanation:
The volume of the composite figure is:
[tex]V = \frac{1}{2}\cdot (3\,u)\cdot (4\,u)\cdot (8\,u) + (5\,u)\cdot (4\,u)\cdot (8\,u)[/tex]
[tex]V = 208\,u^{3}[/tex] (Option C)
Find the lateral surface area of the cylinder. Round your answer to the nearest tenth.
Answer:
[tex]226.2m^2[/tex]
Step-by-step explanation:
[tex]A_L=2\pi rh=2*\pi *4.5*8\\=226.19467\\=226.1947\\=226.195\\=226.2m^2[/tex]
The height of a right square pyramid is multiplied by 6, but the area of the base remains fixed. What is the volume of the taller pyramid divided by the volume of the shorter pyramid ?
Answer:
I’m pretty sure it’s 6 but I’m not 100% sure
Step-by-step explanation:
Answer:
the answer is 6 can you mark me branilist
Step-by-step explanation:
A square has side length (5x-3) cm. What is the area of the square?
Answer:225 cm
Step-by-step explanation:
Square has 4 equal sides
Area of squares equal length x width
If one side length is 5x-3 , the width is the same
Hence -15 x -15
What number is opposite of 98
Answer:
89
Step-by-step explanation:
Answer:
-98
Step-by-step explanation:
Because the negative of the number is on the opposite side of a number line.
Problem 5.
Joseph is told to dissolve a medicine he has to take in 1 pint 4 ounces of water. He has a
measuring cup marked in ounces. How many ounces of water should he pour?
Answer:
The amount of water he should pour in ounces(that is the only units the cup measures) is 16 + 4 = 20 ounces
Step-by-step explanation:
He is told to dissolve a medicine he has in 1 pint 4 ounces of water . He has a measuring cup marked in ounces .This means he can only measure the water quantity in ounces.
He definitely have to convert the pints to ounces.
1 pint = 16 ounces
Recall he has to dissolve the medicine in 1 pint 4 ounces of water.
Since 1 pint is equals to 16 ounces therefore, 16 ounces + 4 ounces = 20 ounces.
The amount of water he should pour in ounces(that is the only units the cup measures) is 16 + 4 = 20 ounces
Calculate the indicated value of each function. f(x) = –15x^2+9. Find f(12).
Answer:
-2151
Step-by-step explanation:
f(x) = –15x^2+9.
Let x = 12
f(12) = -15 ( 12)^2 +9
= -15 (144) +9
= -2151
Answer:
-2151
Step-by-step explanation:
F(x) = -15x^2 + 9
F(12) = -15 (12)^ 2 + 9
= -15 * 144 + 9
= -2160 + 9
= -2151
Find 6% of $3,020.
People please
Answer:
$181.20
Step-by-step explanation:
6% of $3,020 is $3,020. I don't really know how to explain it but yeah lol.
Answer:
Your answer is 181.2
Step-by-step explanation:
the number 3020 is 100% (because it's the output value of the task)
If 3020 is 100%, so we can write it down as 3020=100%.
We know, that x is 6% of the output value, so we can write it down as x=6%.
Now we have two simple equations:
3020=100%
x=6%
3020/x=100%/6%
Now we just have to solve the simple equation, and we will get the solution we are looking for.
3020/x=100/6
(3020/x)*x=(100/6)*x (we multiply both sides of the equation by x)
3020=16.666666666667*x (we divide both sides of the equation by) (16.666666666667) to get x
3020/16.666666666667=x
181.2=x
x=181.2
hope this helps
Give Brainliest if you please
A recent research study randomly divided participants into groups who were given different levels of Vitamin E to take daily. One group received only a placebo pill. The research study followed the participants for eight years to see how many developed a particular type of cancer during that time period. Which of the following responses gives the best explanation as to the purpose of randomization in this studyA. To increase the accuracy of the research results B. To ensure that all potential cancer patients had an equal chance of beng selected for the study. C. To reduce the amount of sampling error D. To produce treatment groups with similar characteristics E. To prevent skewness n the resuits. F. I am not familiar with this matorial
Answer: D. To produce treatment groups with similar characteristics
Step-by-step explanation:
By using randomization in sampling, the Sample would be more representative of the Population it is based off of because different demographic characteristics may be picked.
This leads to a situation where the groups have similar characteristics between themselves thereby making it easier for comparison. For example, Group 1 would have certain types of people that will be represented in Group 2 and Group 3 as well. That way the effects of the drug can be properly studied as it affects different people. For instance, say there are 4 obese people in a sample of 10, instead of group one having all obese people, randomization may be able to give group one, 2 obese people and 2 obese people to group 2 as well. That way when comparing, the effects of the drug on the two groups is easier to be compared because the two groups have similar people.
Answer with explanation will mark brainliest
for best response
Answer:
Angle B = 106.6 degrees
Step-by-step explanation:
b^2= a^2+c^2-2*a*c*cosB
9*9 = 4*4 + 7*7 - 2*7*4*cosB
81= 16+49-56cosB Subtract 16 and 49 from both sides
16= -56cosB Divide by -56 on both sides.
cosB= -16/56 Take the arccosine of both sides
B=arccos(-16/56)
B= 106.6
Answer:
B. 106.6
Step-by-step explanation:
To solve for angle B, we can use the law of cosines.
Recall that the law of cosines states [tex]b^2=a^2+c^2-2ab*cos(B)[/tex]
When this is solved for angle B, we get [tex]B=cos^{-1}( \frac{a^2+c^2-b^2}{2ac} )[/tex]
In this triangle, [tex]a=7, b=9, c=4[/tex]
Now, we can plug these numbers into our equation and then simplify to get B.
[tex]B=cos^{-1}( \frac{7^2+4^2-9^2}{2(7)(4)} )\\\\B=cos^{-1}( \frac{49+16-81}{56} )\\\\B=cos^{-1} (\frac{-16}{56} )\\\\B=106.602\\\\B=106.6[/tex]