True or false:
a. A product of two self-adjoint matrices is self-adjoint.
b. If A is self-adjoint, then Ak is self-adjoint.
Justify your conclusions
Answer:
Option a is "False".
Option b is "True".
Step-by-step explanation:
In point a:
Prove AB=BA
[tex]A=\left[\begin{array}{cc}1&2\\4&5\end{array}\right] \\\\B= \left[\begin{array}{cc}2&1\\8&5\end{array}\right][/tex]
Solve L.H.S part:
[tex]AB= \left[\begin{array}{cc}1&2\\4&5\end{array}\right] \times \left[\begin{array}{cc}2&1\\8&5\end{array}\right][/tex]
[tex]= \left[\begin{array}{cc}2+16 &1+10\\8+40&4+25\end{array}\right]\\\\\\= \left[\begin{array}{cc}18 &11\\48&29\end{array}\right][/tex]
Solve R.H.S part:
[tex]BA= \left[\begin{array}{cc}2&1\\8&5\end{array}\right] \times \left[\begin{array}{cc}1&2\\4&5\end{array}\right][/tex]
[tex]= \left[\begin{array}{cc}2+4 &4+5\\8+20&16+25\end{array}\right]\\ \\ \\= \left[\begin{array}{cc}6 &9\\28&41\end{array}\right][/tex]
So, [tex]AB \neq BA[/tex]
In point b:
[tex]A^{*} =A\\\\(Ak)^{*} =A^k[/tex]
if [tex]k= 1[/tex]it holds the trivially [tex]A^{*}=A ...........(1)[/tex]
by assuming that if it is true for [tex]k=n-1[/tex]
that is
[tex](A^{n-1})^{*}= A^{n-1}............(2) \\\\ if \ k=n\\\\\to (A^{n})^{*} = (A^{n-1} \cdot A^1)^{*} = A^{*}(A^{n-1})^{*} \\\\\to A(A)^{n-1}[/tex] use above equations
[tex]\to A^{n-1+1} \\\\ \to A^{n}[/tex]
that's why it is true.
Devante has a lunch account in the school cafeteria. His starting balance at the beginning of the month in $35.50. The first week, Devante bought 3 lunches and his account balance was $28.00. The second week, Devante bought 5 lunches and his account balance was $15.50.
In a model that relates the balance of his lunch account as a function of the number of lunches he buys, what does the rate of change represent?
A) the number of lunches he purchases
B) The starting balance of his lunch account
C) The amount of money in his lunch account
D) The amount of money he pays for each lunch
Answer:
C) The amount of money in his lunch account
Step-by-step explanation:
Which postulate or theorem can be used to prove ABC = DCB
Answer:
SSS theorem
Step-by-step explanation:
SSS theorem
You only have 30 hours of vacation time left I always work 8 hours per day so that mean that I can take how many days off
Answer:
2
Step-by-step explanation:
HELP ME PLEASEEEEEEEEEEEE !!!!!
Which of these statements are true for the parabola shown here? Select all that apply. Selecciona todas las que correspondan)
Vertex on the y-axis
Concave down
One positive x-intercept
One negative y-intercept
Line of symmetry at y = 3
Answer:
so 3×2 is 839 and 828 equal to pie 111+×÷ equals for the equation is the awnser to 444 which is 344
A medication contains 5 milligrams/milliliter, and a patient is taking 1 teaspoon of it 3 times daily. How many milligrams of medication is the patient receiving per day?
options:
5 milligrams
7.5 milligrams
75 milligrams
100 milligrams
Answer:
Answer: 75 milligrams
Step-by-step explanation:
The medication contains 5 milligrams/milliliter.
The patient is given 1 teaspoon of the medication 3 times a day. Since 1 teaspoon is approximately equal to 5 milliliters, then the patient takes 3*5 = 15 milliliters of the medication per day.
Each milliliter contains 5 milligrams, thus the patient receives 15*5 = 75 milligrams of medication per day.
Answer: 75 milligrams
The length of a rectangle is (x+3)cm. If the width of the rectangle is two thirds its length and the perimeter is 27cm,find its area
Answer:
[tex]A = 43.74[/tex]
Step-by-step explanation:
Represent Length with L, Width with W and Perimeter with P
[tex]P = 27[/tex]
[tex]L=x+3[/tex]
[tex]W = \frac{2}{3}(x + 3)[/tex]
Required
Determine the Area
From the perimeter, we need to solve for x;
[tex]P = 2(L + W)[/tex]
Substitute values for P, L and W
[tex]27 = 2(x + 3 + \frac{2}{3}(x+3))[/tex]
[tex]27 = 2(x + 3 + \frac{2}{3}x+2)[/tex]
Collect Like Terms
[tex]27 = 2(3 + 2 + x + \frac{2}{3}x)[/tex]
[tex]27 = 2(5 + \frac{3x + 2x}{3})[/tex]
[tex]27 = 2(5 + \frac{5x}{3})[/tex]
Open bracket
[tex]27 = 10 + \frac{10x}{3}[/tex]
Collect Like Terms
[tex]27 - 10 = \frac{10x}{3}[/tex]
[tex]17= \frac{10x}{3}[/tex]
Solve for x
[tex]x = \frac{3*17}{10}[/tex]
[tex]x = \frac{51}{10}[/tex]
[tex]x = 5.1[/tex]
The Area is then calculated using:
[tex]A = L * W[/tex]
[tex]A = (x + 3)*\frac{2}{3}(x+3)[/tex]
[tex]A = \frac{2}{3}(x+3)^2[/tex]
Substitute 5.1 for x
[tex]A = \frac{2}{3}(5.1+3)^2[/tex]
[tex]A = \frac{2}{3}(8.1)^2[/tex]
[tex]A = \frac{2}{3}*65.61[/tex]
[tex]A = \frac{2*65.61}{3}[/tex]
[tex]A = \frac{131.22}{3}[/tex]
[tex]A = 43.74[/tex]
Hence, the area is [tex]43.71cm^2[/tex]
Pleaseeee help me I need help reallly bad
Describe the transformation of ƒ(x) = ex which is given by g(x) = −e2x + 6.
A)
g(x) is reflected across the y-axis and translated 6 units to the right compared to ƒ(x).
B)
g(x) is reflected across the x-axis and translated 6 units up compared to ƒ(x).
C)
g(x) is reflected across the y-axis and translated 6 units to the left compared to ƒ(x).
D)
g(x) is reflected across the x-axis and translated 6 units down compared to ƒ(x).
Answer:
g(x) is reflected across the x-axis and translated 6 units up compared to ƒ(x).
Step-by-step explanation:
Answer:
Step-by-step explanation:
g(x) is reflected across the x-axis and translated 6 units up compared to ƒ(x).
WILL MARK BRAINLIEST
Answer:
48 in²
Step-by-step explanation:
if it's a right triangle you can multiply your sides like uts a rectangle and then divide it by 2. look at the triangle like its half a rectangle
The Serenity and the Mystic are sail boats. The Serenity and the Mystic start at the same point and travel away from each other in opposite directions. The Serenity travels at 16 mph and the Mystic travels at 20 mph. How far apart will they be in 2 hours? A. 52 miles B. 56 miles C. 40 miles D. 72 miles
Answer:
te puedo responder pero debes hacer primero tu tarea
Step-by-step explanation:
What do you think the answer is??
Answer:
c
Step-by-step explanation:
Answer:
it's "b"
Step-by-step explanation:
3
1
The temperature fell from 0°F to 6 3/5 F below 0f in 2 1/5 hours. What was the temperature change per hour?
Answer:
The rate is -3°F per hour.
Step-by-step explanation:
The rate of change of the temperature per hour, will be equal to the quotient between the total change in temperature and the time it took for the change.
We know that the initial temperature is 0°F
The final temperature is -(6 + 3/5)°F
Then the change in the temperature will be:
Final temperature - initial temperature = -(6 + 3/5)°F - 0°F = -(6 + 3/5)°F
We know that this change took a total of (2 + 1/5) hours, then we can conclude that the rate will be:
Rate = -(6 + 3/5)°F/(2 + 1/5) hs = -(30/5 + 3/5)°F/(10/5 + 1/5) hs
= -(33/5)°F/(11/5)hs = -(33/11) °F/hs = -3 °F/hs
This means that the rate of change is -3°F per hour, so the temperature decreases 3 °F for each hour that passes.
wooo i really really loce math
Step-by-step explanation:
REALLLYYY???!!!!!!
JK
thx 4 the points..
The number
5/7
can be best described as a(n)
mixed number
improper fraction
O proper fraction
(1 + 9.8k)(2.8) simplified
Answer:
2.8 + 27.44k
Step-by-step explanation:
Algebraic Simplification
The rules of algebra can be applied in some situations to make expressions simplified or expanded, according to the specific needs of each problem.
We are given the expression:
(1 + 9.8k)(2.8)
It's a sum and a product. We cannot add the independent term with the variable term, so we can only multiply the factor and the contents of the parentheses as follows:
(2.8)1 + (2.8)9.8k
Operating:
2.8 + 27.44k
Given that the population proportion is 0.82, the Normal distribution will provide a good approximation to the true sampling distribution of the sample proportion as long as:________.
A) n> 13.
B) n> 30.
C) n> 56.
D) n > 100.
Answer:
Then solution as long as n ≥ 56
Step-by-step explanation:
The Normal distribution will provide a good approximation to evaluate proportion tests when the following conditions are met:
n*p₀ > 10
n*q₀ > 10
As p₀ = 0,82 q₀ = 0,18 n = 13 30 56 and 100
We test:
A) n = 13 n*q₀ = 13*0,18 = 2,34 2,34 < 10
B) n = 30 n*q₀ = 30*0,18 = 5,4 5,4 < 10
C) n = 56 n*q₀ = 56 * 0,18 = 10,08
n*p₀ = 56 * 0,82 = 45,92
D) n = 100 n*q₀ = 18
n*p₀ = 82
If we test 55 we find that 55*0,18 = 9,9
Then solution as long as n ≥ 56
Alina and Asim share 210 dollars In the ratio 2:5 how much money did each of them get ?
Answer:
Let Alina share be 2x and asking share be 5x
then, 2x+5x =210 dollars
7x =210 dollars
x=30 dollars
then share of Alina = 2x = 2 * 30 = 60 dollars
and share of asim= 5x = 5 * 30 = 150 dollars
Answer:
I hope the above pic will help you I have done it in word
I will always help you understanding your assingments
have a great day
#Captainpower:)
the height of an object after t seconds is given by f(t)=-5t^2+20t (a) find the height of the object after 2 seconds, and include the correct units with your answer. (b) find the average (vertical) velocity of the object on the time interval [0,2]. show your work, include the correct units, and. circle your final answer. (c) find the instantaneous velocity at t=2
Answer:
t=20 4=5 =6 =8 =9 10
Step-by-step explanation:
And that is iy
a. A bicycle shop marks down each bicycle's selling price b by 22% for a holiday sale.
b. What is a single term expression for the sale price?
The expression for the sale price is ____?
9514 1404 393
Answer:
0.78b
Step-by-step explanation:
The sale price will be ...
b - 22% × b = b(1 -22%) = b(1 -0.22)
= 0.78b . . . . single-term expression for sale price
Please help me thank you I appreciate
Answer:
90-34=56° .....................
How to solve it&&&&&&&&&&&
Answer:
y = 4 and x = 12
Step-by-step explanation:
Step by step explanation in the pic. Atleast the way I did it.
Michelle had 600 fish to feed the dolphins in a zoo. Each dolphins ate the same number of fish. There are 9 dolphins in all. How many fish did Michelle have left?
PLEASE HELP URGENT WILL GIVE BRAINLIEST
Answer:
Please check the explanation.
Step-by-step explanation:
We know that
An expression can not be a polynomial if any term has a negative exponentAn expression can not be a polynomial if any term has a fraction exponentAn expression can not be a polynomial if any term contains division by a variable.2)
Given the expression
f(x) = 3x + 4/3 x³ - 7
The given expression is a polynomial with degree 3 (highest power of any variable) and having 3 terms
3)
Given the expression
g(x) =- 5x³ + x - 3/x
The given expression is NOT a polynomial as any term of a polynomial can not have exponent as -1.
For example, the term 3/x or 3x⁻¹ has negative exponent -1.
Thus, g(x) =- 5x³ + x - 3/x
4)
Given the expression
h(x) =x³√5 + x - 3
The given expression is a polynomial with degree 3 (highest power of any variable) and having 3 terms
5)
Given the expression
k(x)=25x²-x³+x⁵
The given expression is a polynomial with a degree of 5 (highest power of any variable) and having 3 terms.
Angie divides the polynomial function f (x)+x3+3x2-7x-21 by (x+3) what can she conclude from the fact that the remainder is equal to 0
Answer:
Yes, and if you divide x^3+3x^2-7x-21 with x+3 you will result in x^2-7
Step-by-step explanation:
Hope this helps
And I like your profile pic
The given polynomial is divisible by x+3 because f(-3)=0
So , the remainder is equal to 0
Her conclusion is correct.
Given :
Angie divides the polynomial function
[tex]f (x)=x^3+3x^2-7x-21[/tex] by (x+3)
Apply remainder theorem to check whether the remainder is equal to 0
If a polynomial p(x) is divisible by (x-a), the remainder obtained is P(a)
x+3 is the divisor
Lets set the divisor =0 and solve for x
[tex]x+3=0\\x=-3[/tex]
Now we plug in -3 for x in given f(x) and see whether f(-3) =0
[tex]f (x)=x^3+3x^2-7x-21\\f (-3)=(-3)^3+3(-3)^2-7(-3)-21\\f(-3)=-27+27+21-21\\f(-3)=0[/tex]
So, f(-3)=0 and hence the remainder is 0
Her conclusion is correct
Learn more : brainly.com/question/19908280
I need to understand question 14 and 15 and the last one cut off for tens in one
Question # 14
Given the numbers
10 11 12 13 14 15 16 17 18 19 20
Let 'x' be the number
The condition breakdown:
I am less than 20.
So the number 'x' must be less than 20 i.e. x < 20I am more than 13.
So the number 'x' must be greater than 13 i.e. x > 13I am less than 17.
So the number 'x' must be less than 17 i.e. x < 17Finally:
I am 4 more than 12
i.e. 12+4 = 16
Thus, the number is x = 16
Question # 15
Part a)
Given the numbers
10 11 12 13 14 15 16 17 18 19 20
Let 'x' be the number
The condition breakdown:
I am more than 10.
x > 10I am less than 20.
x < 20I am more than 12.
x > 12I am less than 15.
x < 15As the numbers left after all the conditions are fulfilled are 13 and 14.
But the last condition is, of the numbers that left, the number is greater than all the remaining numbers.So, from the remaining number 13 and 14;
14 > 13
Thus, the number x = 14
Part b)
Drawing the number 14 in the place value:
Chart
Tens Ones
1 4
Suppose that Bob can decide to go to work by one of the three modes of transportation; car, bus, or train. Because of high traffic, if he decides to go by car, there is a 50% chance he will be late. If he goes by bus there is a 20% chance he will be late. If he goes by train there is only 1% chance that he will be late. Suppose he takes the car 10% of the time, the bus 1% of the time, and the train 89% of the time, What is the probability that Bob will be late getting to work?
The probability is (0.10 * 0.50 + 0.01 * 0.20 + 0.89 * 0.01) * 100% = 6.09%.
skateboard is priced for $38. They are having a sale for 20% off. how much is the discount and what is the selling price
Answer:
18$
Step-by-step explanation:
Please help me and show work
Answer:
2/5
Step-by-step explanation:
If we convert 1/2 to tenths we get 5/10. We can subtract that from 9/10 to find out what q equals which will give us 4/10 which is also equal to 2/5
(sorry i'm really bad at explaining but I hope this helps)