Rewrite, using the distributive
property (Algebra 1)

Use the definitions of expectation and variance.

[tex]E(X) = \displaystyle \int_{-\infty}^\infty x f_X(x) \, dx = \frac14 \int_0^\infty x e^{-x/4} \, dx[/tex]

Integrate by parts,

[tex]\displaystyle \int_a^b u \, dv = uv \bigg|_a^b - \int_a^b v \, du[/tex]

with

[tex]u = x \implies du = dx \\\\ dv = e^{-x/4} \, dx \implies v = -4 e^{-x/4}[/tex]

Then

[tex]E(X) = \displaystyle \frac14 \left(\left(-4x e^{-x/4}\right)\bigg|_0^\infty + 4 \int_0^\infty e^{-x/4} \, dx\right)[/tex]

[tex]E(X) = \displaystyle \int_0^\infty e^{-x/4} \, dx = \boxed{4}[/tex]

(since the integral of the PDF is 1, and this integral is 4 times that)

[tex]V(X) = E\bigg((X - E(X))^2\bigg) = E(X^2) - E(X)^2[/tex]

Compute the so-called second moment.

[tex]E(X^2) = \displaystyle \int_{-\infty}^\infty x^2 f_X(x)\, dx = \frac14 \int_0^\infty x^2 e^{-x/4} \, dx[/tex]

Integrate by parts, with

[tex]u = x^2 \implies du = 2x \, dx \\\\ dv = e^{-x/4} \, dx \implies v = -4 e^{-x/4}[/tex]

Then

[tex]E(X^2) = \displaystyle \frac14 \left(\left(-4x^2 e^{-x/4}\right)\bigg|_0^\infty + 8 \int_0^\infty x e^{-x/4} \, dx\right)[/tex]

[tex]E(X^2) = 8 E(X) = 32[/tex]

and the variance is

[tex]V(X) = 32 - 4^2 = \boxed{16}[/tex]

Step-by-step explanation:

[tex]f(x) = 6 {x}^{2} - 4[/tex]

[tex]g(x) = 2x + 2[/tex]

[tex] \: [/tex]

[tex] = (f - g)(x)[/tex]

[tex] = f(x) - g(x)[/tex]

[tex] = 6 {x}^{2} - 4 - (2x + 2)[/tex]

[tex] = 6 {x}^{2} - 4 - 2x - 2[/tex]

[tex] = 6 {x}^{2} - 2x - 4 - 2[/tex]

[tex] = 6 {x}^{2} - 2x - 6[/tex]

[tex](f - g)(x) = 6 {x}^{2} - 2x - 6[/tex]

Answer:  (5/1, -3)

Hope this helps :)

Answer:

Look at the attachment.

Step-by-step explanation:

Look at the attachment.

Step-by-step explanation:

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Answer:

(x - 3) is a factor of the given function

Step-by-step explanation:

Given function:

[tex]\implies f\:\!\:(x)=x^3-x^2-5x-3[/tex]

If (x - 3) is a factor of the given function then [tex]f\:\!\:(3) = 0[/tex]

Substitute x = 3 into the function and solve:

[tex]\implies f\:\!\:(3)=(3)^3-(3)^2-5(3)-3[/tex]

[tex]\implies f\:\!\:(3)=27-9-15-3[/tex]

[tex]\implies f\:\!\:(3)=0[/tex]

Therefore, as  [tex]f\:\!\:(3) = 0[/tex] then (x - 3) is a factor of the given function.

The correct graph of the following condition. {(x, y) : x - y6} is depicted in the graph attached.

A graph is a diagram showing the relation between variable quantities each measured along one of a pair of axes at right angles.

In this case, the correct graph of the following condition. {(x, y) : x - y6} is depicted in the graph attached.

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Answer:

The answer will be J

Step-by-step explanation:

Since you see, that the 67,896 will need to be rounded. It rounds up to 70,000 so you can elinmate M & N. 22% can be converted as a decimal to 0.2, also equals to 0.20. So elinmate L. Now you have J and K. You always times with these kinds of percentage.

Therefore the Answer Will Be J: 70,000 timed by 0.20.

Expert-Certifieder of Cousin.

Based on the required width and height of the tent, the length of the cloth would have to be 14.4 ft.

The opening of the tent would be an isosceles triangle but if it is divided in two from the top, a right-angled triangle will be formed and the hypotenuse will be the length of the cloth on one side.

That length - according to the Pythagoras theorem - would be:

= √(6² + (8 /2)²)

= √(36 + 16)

= 7.2 ft

As this is the length of one side of the cloth, the length of the entire cloth is:

= 7.2 x 2

= 14.4 ft

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Answer:

A.4

Step-by-step explanation:

Using the sine rule

sin(α)/A equals sin(β)/B

From the question & inserting values,

sin(90°)/8 equals sin(30°)/x

∴x equals[tex]\frac{sin(30)}{sin(90)}[/tex]×8

∴x equals 4

You can learn more on the sine rule in case you get confused.

Answer:

A

Step-by-step explanation:

using the sine ratio in the right triangle and the exact value

sin30° = [tex]\frac{1}{2}[/tex] , then

sin30° = [tex]\frac{opposite}{hypotenuse}[/tex] = [tex]\frac{x}{8}[/tex] = [tex]\frac{1}{2}[/tex] ( cross- multiply )

2x = 8 ( divide both sides by 2 )

x = 4

Answer:

A

Step-by-step explanation:

By looking at the graph you can eliminate B as a choice since the denominator is 1+x which means it would have a vertical asymptote as x=-1 which doesn't correspond with the graph shown. You can also eliminate C since the function doesn't have a vertical asymptote as x=3 since the denominator of the function is 3-x meaning it would be undefined at x=3. It should be A since it appears to approaching 1 with a vertical asymptote at x=1 which corresponds with the denominator 1-x. If you plug in the value 0 as x you get 3 which is what is shown on the graph when x equals 0

A tessellation that uses only one type of regular polygon.

The definition of a polygon is given as a closed two-dimensional figure with three or more straight lines.

When we cover a surface with a pattern of a flat geometric shapes such that there should have no overlaps or gaps, then the surface is called a tessellation.

A regular tessellation is tessellation made up by using only one type of regular polygon. These are made up of entirely congruent regular polygons all that joining vertex to vertex.

Hence, A is the correct option.

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Answer:

The answer is 5

Because 200÷10 =20.

So I'm this case, 4x=20. Divide both sides by 4 and the answer is 5. So X=5

5

Answer:

Step-by-step explanation:

if 200÷10=4×u then u=?​

200 : 10 = 4u

20 = 4u

u = 20 : 4

u = 5

---------------------------

check

200 : 10 = 4 * 5

20 = 20

the answer is good

A function assigns the values. The correct option is D.

A function assigns the value of each element of one set to the other specific element of another set.

The complete question is:

Which pair of statements describe the end behavior of the graph of the function f(x) = x³ + 2x² − 5x − 6?

A.) As x approaches negative infinity, f(x) approaches infinity. As x approaches infinity, f(x) approaches infinity.

B.) As x approaches negative infinity, f(x) approaches infinity. As x approaches infinity, f(x) approaches negative infinity.

C.) As x approaches negative infinity, f(x) approaches negative infinity. As x approaches infinity, f(x) approaches negative infinity.

D.) As x approaches negative infinity, f(x) approaches negative infinity. As x approaches infinity, f(x) approaches infinity.

If we draw the graph of the given function f(x) = x³ + 2x² − 5x − 6, then it can be observed that as x approaches -∞, f(x) approaches -∞. As x approaches ∞, f(x) approaches infinity.

Hence, the correct option is D.

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log was used calculate big numbers before calculators

log is a re-arranged way to show a number with an exponent

example

log₂ 16 = 4 means 2^4 = 16

logx(Z) = y means x^y=Z

log(x-6)/log(2) + log(x)/log(2) = 4

(log(x-6)+ log(x))/log(2) = 4

(log(x-6)+ log(x)) = 4log(2)

(log(x-6)x) = log(16)

x=8

The solution of the system of linear equation by substitution method is (3,1).

The method of substitution is the method for solving the linear equation where the value of one variable of one equation is placed in the place of that variable in another equation.

Given here the linear equations are

Equation 1: 6x+2y=20

Equation 2: 2x-3y=3

in equation 1 the value of y will be

6x+2y=20

⇒2y=20-6x

⇒y=(20-6x)/2

⇒y=10-3x

substituting the value of y in the equation 2, we will get

2x-3y=3

⇒2x-3(10-3x)=3

⇒2x-30+9x=3

⇒11x-30=3

⇒11x=30+3

⇒11x=33

⇒x=33/11

⇒x=3

putting the value of x in value of y in equation 1

y=10-3x

⇒y=10-3(3)

⇒y=10-9

⇒y=1

The solution of the system of linear equation by substitution method is (3,1).

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The value of x in the right angle triangle is 45 / 4 units

AB² = 20² - 15²

AB = √400 - 225

AB = √175

AB = √175 units

Hence, using similarity ratio,

x / 15 = 15 / 20

cross multiply

20x = 225

x = 225 / 20

x = 45 / 4

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Answer:

Answer:

10

Step-by-step explanation:

15 ÷ 1.5 = 10

Considering the result of the expression of the square of the sum,  2(2n² + 2)  is always an even number, then when 1 is added it will always be an odd number.

It is given as follows:

(a + b)² = a² + 2ab + b².

In this problem, the expression is:

(2n + 1)² = (2n)² + 2(2n)(1) + 1²

             = 4n² + 4n + 1

             = 2(2n² + 2) + 1

The term 2(2n² + 2) will always be even(multiplication by 2), and when 1 is added to an even number it will always be odd, hence it is proved that an  odd number squared is an odd number.

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Solving a quadratic equation, the age of the man with a blood pressure of 125 mmHg is of 27 years old.

A quadratic function is given according to the following rule:

[tex]y = ax^2 + bx + c[/tex]

The solutions are:

In which:

[tex]\Delta = b^2 - 4ac[/tex]

The pressure is given by:

P = 0.006A² - 0.02A + 120.

When the pressure is of 125 mmHg, we have that:

0.006A² - 0.02A + 120 = 125.

0.006A² - 0.02A - 5 = 0.

Hence the coefficients are a = 0.006, b = -0.02, c = -5, and the solutions, applying the formula are:

A = -30 and A = 27.

Age has to be positive, hence the man is 27 years old.

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Answer:

I believe that it should be Y; Height of an emperor penguin on Antarctica

Answer:

Z = "results of flipping two coins"

Step-by-step explanation:

A discrete variable is one which can take only certain values and usually represents values that are counted. The result of flipping two coins can only take a certain number of values of heads or tails (1 head and 1 tail, two heads, or two tails); therefore it is a discrete variable.

A continuous variable is one which can take any value, and usually represents values that are measured. The rest of the options provided (W, X, and Y) are all measurements, and are therefore continuous, not discrete.

Also, among the options presented, option Z is the only one which is "random".

Hey there!

-9x + 4 < 40

SUBTRACT 4 to BOTH SIDES

-9x + 4 - 4 < 40 - 4
SIMPLIFY IT!

-9x < 40 - 4

-9x < 36

DIVIDE -9 to BOTH SIDES

-9x/-9 < 36/-9

SIMPLIFY IT!

x < 36/-9

x < -4

Therefore, the answer should be:

x < -4

(The graph is down below)

Good luck on your assignment & enjoy your day!

~Amphitrite1040:)

Answer:

2

Step-by-step explanation:

In asin(bx - c) + d, a is the amplitude. In this case, it's 2.

Brainliest, please :)

The time taken for Terick to run one complete mile is determined as 12 minutes

The speed of chad is calculated as follows;

s = distance/time

s = (3.25 miles)/(40)

s = 0.08125 miles/min

2/3 of a mile = 8 mins

1/3 of a mile = ?

1/3 of a mile  =  4mins

1 mile = 8 mins + 4 mins = 12 mins

Thus, the time taken for Terick to run one complete mile is determined as 12 minutes.

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Answer:

area:3116  perimeter:240

Step-by-step explanation:

Hii!

__________________________________________________________

[tex]\stackrel\star{\rightsquigarrow\circ\boldsymbol{\underbrace{Answer:}\circ\leftharpoonup}}[/tex]

Pelet'rimeter =

Area = 3116 cm^2

[tex]\stackrel\star{\rightsquigarrow\circ\boldsymbol{\underbrace{Explanation:}\circ\leftharpoonup}}[/tex]

[tex]\bullet[/tex] Let's work out the perimeter

[tex]\twoheadrightarrow\sf P=2(a+b)[/tex]. a=length & b=width

[tex]\bullet[/tex] Stick in the values

[tex]\twoheadrightarrow\sf P=2(82+38)[/tex]

[tex]\bullet[/tex] Perform the addition operation

[tex]\twoheadrightarrow\sf P=2\cdot120[/tex]

[tex]\bullet[/tex] Multiply and obtain the perimeter

[tex]\twoheadrightarrow\sf P=240cm[/tex]

[tex]\bullet[/tex] Now let's find the area

[tex]\twoheadrightarrow\sf A=lw[/tex] l=length w=width

[tex]\bullet[/tex] Stick in the values

[tex]\twoheadrightarrow\sf A=82\cdot38[/tex]

[tex]\bullet[/tex] Multiply and obtain the area

[tex]\twoheadrightarrow\sf A=3116cm^2[/tex]

--

Hope that this helped! Best wishes.

[tex]\stackrel\star{\textsl{Reach far. Aim high. Dream big.}}[/tex]

--

Answer: 110 degrees

Step-by-step explanation:

By the exterior angle theorem.

[tex]10x-10=100-2x+2x+10\\\\10x-10=110\\\\\therefore \angle ABC=110^{\circ}[/tex]

Answer:

[tex]-6.5x+11[/tex]

Step-by-step explanation:

Expand The Brackets:

[tex]x-1+12-7.5x[/tex]

[tex]=x+(-1)+12+(-7.5x)[/tex]

Combine Like Terms:

[tex]=x+(-1)+12+(-7.5x)[/tex]

[tex]=(x+-7.5x)+(-1+12)[/tex]

Answer:

[tex]-6.5x+11[/tex]

I Hope This Helps