How would I do this?

Arithmetic Sequence

'nth' term of each

i)n^2+2n

ii) n^2- 2n​

1) Sum of first n terms = n² + 2n

We know that,

Sum of first n terms = n/2 * [ a + l ]

Where,

a is first term

l is nth or last term.

Substitute n = 1 to find the sum of first 1 terms i.e., first term (a) of the AP.

→ S₁ = a = (1)² + 2(1)

→ a = 1 + 2

→ a = 3

Hence,

→ n/2 * [ a + l ] = n² + 2n

→ a + l = n(n + 2) * 2/n

→ a + l = 2n + 4

→ l = 2n + 4 - a

→ l = 2n + 4 - 3

→ l = 2n + 1

Hence, the nth term is 2n + 1.

2)S(n) = n² - 2n

→ S₁ = a = (1)² - 2(1)

→ a = - 1

Hence,

→ n/2 * [ - 1 + l ] = n² - 2n

→ l - 1 = n(n - 2) * 2/n

→ l - 1 = 2n - 4

→ l = 2n - 4 + 1

→ l = 2n - 3

Hence, the nth term is 2n - 3.

I hope it will help you.

Regards.

Step-by-step explanation:

Series

The series of a sequence is the sum of the sequence to a certain number of terms. It is often written as Sn. So if the sequence is 2, 4, 6, 8, 10, ... , the sum to 3 terms = S3 = 2 + 4 + 6 = 12.

The Sigma Notation

The Greek capital sigma, written S, is usually used to represent the sum of a sequence. This is best explained using an example:

This means replace the r in the expression by 1 and write down what you get. Then replace r by 2 and write down what you get. Keep doing this until you get to 4, since this is the number above the S. Now add up all of the term that you have written down.

This sum is therefore equal to 3×1 + 3×2 + 3×3 + 3×4 = 3 + 6 + 9 + 12 = 30.

3

S 3r + 2

r = 1

This is equal to:

(3×1 + 2) + (3×2 + 2) + (3×3 + 2) = 24 .

The General Case

n

S Ur

r = 1

This is the general case. For the sequence Ur, this means the sum of the terms obtained by substituting in 1, 2, 3,... up to and including n in turn for r in Ur. In the above example, Ur = 3r + 2 and n = 3.

Arithmetic Progressions

An arithmetic progression is a sequence where each term is a certain number larger than the previous term. The terms in the sequence are said to increase by a common difference, d.

For example: 3, 5, 7, 9, 11, is an arithmetic progression where d = 2. The nth term of this sequence is 2n + 1 .

In general, the nth term of an arithmetic progression, with first term a and common difference d, is: a + (n - 1)d . So for the sequence 3, 5, 7, 9, ... Un = 3 + 2(n - 1) = 2n + 1, which we already knew.

The sum to n terms of an arithmetic progression

This is given by:

Sn = ½ n [ 2a + (n - 1)d ]

You may need to be able to prove this formula. It is derived as follows:

The sum to n terms is given by:

Sn = a + (a + d) + (a + 2d) + … + (a + (n – 1)d) (1)

If we write this out backwards, we get:

Sn = (a + (n – 1)d) + (a + (n – 2)d) + … + a (2)

Now let’s add (1) and (2):

2Sn = [2a + (n – 1)d] + [2a + (n – 1)d] + … + [2a + (n – 1)d]

So Sn = ½ n [2a + (n – 1)d]

Example

Sum the first 20 terms of the sequence: 1, 3, 5, 7, 9, ... (i.e. the first 20 odd numbers).

S20 = ½ (20) [ 2 × 1 + (20 - 1)×2 ]

= 10[ 2 + 19 × 2]

= 10[ 40 ]

= 400

Geometric Progressions

A geometric progression is a sequence where each term is r times larger than the previous term. r is known as the common ratio of the sequence. The nth term of a geometric progression, where a is the first term and r is the common ratio, is:

arn-1

For example, in the following geometric progression, the first term is 1, and the common ratio is 2:

1, 2, 4, 8, 16, ...

The nth term is therefore 2n-1

The sum of a geometric progression

The sum of the first n terms of a geometric progression is:

a(1 - rn )

1 – r

We can prove this as follows:

Sn = a + ar + ar2 + … + arn-1 (1)

Multiplying by r:

rSn = ar + ar2 + … + arn (2)

(1) – (2) gives us:

Sn(1 – r) = a – arn (since all the other terms cancel)

And so we get the formula above if we divide through by 1 – r .

Example

What is the sum of the first 5 terms of the following geometric progression: 2, 4, 8, 16, 32 ?

S5 = 2( 1 - 25)

1 - 2

= 2( 1 - 32)

-1

= 62

The sum to infinity of a geometric progression

In geometric progressions where |r| < 1 (in other words where r is less than 1 and greater than –1), the sum of the sequence as n tends to infinity approaches a value. In other words, if you keep adding together the terms of the sequence forever, you will get a finite value. This value is equal to:

a

1 – r

Example

Find the sum to infinity of the following sequence:

1 , 1 , 1 ,

1

,

1

,

1

, ...

2 4 8 16 32 64

Here, a = 1/2 and r = 1/2

Therefore, the sum to infinity is 0.5/0.5 = 1 .

So every time you add another term to the above sequence, the result gets closer and closer to 1.

Harder Example

The first, second and fifth terms of an arithmetic progression are the first three terms of a geometric progression. The third term of the arithmetic progression is 5. Find the 2 possible values for the fourth term of the geometric progression.

The first term of the arithmetic progression is: a

The second term is: a + d

The fifth term is: a + 4d

So the first three terms of the geometric progression are a, a + d and a + 4d .

In a geometric progression, there is a common ratio. So the ratio of the second term to the first term is equal to the ratio of the third term to the second term. So:

a + d = a + 4d

a a + d

(a + d)(a + d) = a(a + 4d)

a² + 2ad + d² = a² + 4ad

d² - 2ad = 0

d(d - 2a) = 0

therefore d = 0 or d = 2a

The common ratio of the geometric progression, r, is equal to (a + d)/a

Therefore, if d = 0, r = 1

If d = 2a, r = 3a/a = 3

So the common ratio of the geometric progression is either 1 or 3 .

Answer:

x_>0,_>3000

Step-by-step explanation:

I saw the answer key :)

The domain of a function is the set of input values the function can take.

The reasonable domain of the function is [0,16]

From the question, we understand that x represents the number of years after 2000 until 2016.

Hence, the reasonable domain of the function is [0,16]

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Answer:

la respuesta correcta es laC

han ku po ammo paumahin

Answer: D 3sqrt2

Step-by-step explanation:

6x3=18

Sqrt of 18 = 3sqrt2

Answer:

yes

Step-by-step explanation:

same slope

Answer:

yes same slope

Step-by-step explanation:

Step-by-step explanation:

b - no:of students on bus

V - " " on van

so the eqtn is

12v+10b=698

14v+2b=244

so when you solve these two eqtns you get

V=9

b=59

Answer: X=2.9

Step-by-step explanation:

Answer:y=4

Step-by-step explanation:

Answer:

The cost of a can of popcorn is $10.

The cost of a box of cookies is $5.

The cost of a can of popcorn is $20

Step-by-step explanation:

First you must propose a system of equations, a set of two or more equations with several unknowns in which you want to find the value of each unknown so that all the equations of the system are fulfilled.

Defining the variables:

Amy sold 2 pounds of candy, 3 boxes of cookies and 1 can of popcorn for a total sale of $65. Then:

2*x + 3*y + 1*z=65 Equation 1

Brian sold 4 pounds of candy, 6 boxes of cookies and 3 cans of popcorn for a total sale of $140. So:

4*x + 6*y + 3*z=140 Equation 2

Paulina sold 8 pounds of candy, 8 boxes of cookies and 5 cans of popcorn for a total sales of $250. Then:

8*x + 8*y + 5*z=250 Equation 3

Then the system of equations is formed by these three equations.

A method to solve a system of equations is by means of the substitution method, which consists of isolating one of the two unknowns in an equation to substitute it in the other equation.

Isolating z from Equation 1:

[tex]z=65-2*x-3*y[/tex] Equation 4

Replacing in Equation 2:

4*x + 6*y + 3*(65 -2*x-3*y)=140

4*x + 6*y + 195 - 6*x  - 9*y= 140

-2*x - 3*y=140-195

-2*x - 3*y=-55

2*x + 3*y= 55

and isolating x:

[tex]x=\frac{55-3*y}{2}[/tex] Equation 5

Replacing in Equation 4:

[tex]z=65-2*\frac{55-3*y}{2} -3*y[/tex]

z=65 - (55-3*y) - 3*y

z= 65 -55 + 3*y - 3*y

z= 10

So the cost of a can of popcorn is $10.

Replacing equation 5 and the value of z in equation 3:

8*[tex]\frac{55-3*y}{2}[/tex] + 8*y + 5*10=250

[tex]\frac{8}{2}[/tex]*(55 -3*y)+ 8*y + 5*10=250

4*(55 -3*y)+ 8*y + 5*10=250

4*55 - 4*3*y + 8*y + 50=250

220 - 12*y + 8*y + 50=250

-12*y + 8*y= 250 -220 - 50

-4*y= -20

[tex]y=\frac{-20}{-4}[/tex]

y= 5

So the cost of a box of cookies is $5.

Finally replacing the value of y in Equation 5 you get the value of x:

[tex]x=\frac{55-3*5}{2}[/tex]

[tex]x=\frac{55-15}{2}[/tex]

[tex]x=\frac{40}{2}[/tex]

x=20

Finally, the cost of a can of popcorn is $20

Answer:

[tex] \sqrt{2} - \sqrt{2} = 0[/tex]

0 is real number, rational number, integers, whole numbers,

Answer:

The cost to manufacture 63 chairs, and that cost is 2268.

Step-by-step explanation:

Mathematical Models

The cost to manufacture x chairs is given as the math model:

C(x)=36x

For example, to manufacture 10 chairs, we write:

C(10)=36*10=360

According to the explained above, the statement C(63)=2268 means we are calculating the cost to manufacture 63 chairs, and that cost is 2268.

Answer:

44 km

Step-by-step explanation:

8/5 is the conversion between m and km which is 1.6 and then we can simply multiply 27.5 times 1.6 which is 44 km I hope this helps.

Answer:

72

Step-by-step explanation:

7x7 = 49

49 + 23 = 72

PEMDAS causes the multiplication to come before the addition.

Answer:

it attached in low quality im sorry :((

Answer:

6

Step-by-step explanation:

2+4=6

you need to do the oppsite opporation and that the answer for example x-2=4 just add 2 and 4 and thats the answer that is aslo the same rule as divsion and multiplecation sorry for spelleng mistakes hope this helps!!!!!!

Answer:

the answer it's x=6 i think

Answer:

Greater

Step-by-step explanation:

since it has a 0.0001 and not just 1 its greater 43.5

Answer:

h(2)=6

Step-by-step explanation:

just plug in 2 where you have an x, and you’d have 2 + 6, which equals 6

Answer:

Yes, the probability distribution for the number of years of experience can be modelled by a binomial probability distribution

Step-by-step explanation:

We are told that on a recent sample, the paper claims that 45% of all employees believe their company president possesses low ethical standards.

This means the chance of success is p = 45% = 0.45

Now, 20 of the company's employees are randomly and independently sampled. This means that for any amount of success within this sample number can be represented by;

P(X = x) = C(n, x) × p^(x) × (1 - p)^(n - x)

Where;

x is the number of possible successes

n is the number of trials

p is the chance or probability of success

C(n, x) is the number of possible combinations that could occur

This formula represents the binomial probability distribution formula.

So yes, the probability distribution for the number of years of experience can be modelled by a binomial probability distribution

Answer:

0.2143

Step-by-step explanation:

Let A be the event denote that getting into a car accident and B be the event denote being a texter-and-driver.

Thus, P(A)=0.04, P(B)=0.14.

P(A or B)=0.15.

We have to find P(A/B).

P(A/B)=P(A and B)/P(B)

P(A and B)= P(A)+P(B)-P(A or B)

P(A and B)=0.04+0.14-0.15

P(A and B)=0.03.

Thus, P(A/B)=0.03/0.14

P(A/B)=0.2143 (rounded to four decimal places)

Thus, the probability a person was in a car accident given that they are a texter-and-driver is 0.2143. This probability is higher than the probability among the general population because texting while driving is fatal.

Answer:

im going to say 4 hope it helps

Step-by-step explanation:

The required x-intercept and y-intercept of the given line in the graph are 1 and -2 respectively.

The intercept of the line is defined as points where the line intersects the principle axes.

Here,
The x-intercept and y-intercept of the line are defined as the points where the given line cuts the coordinate axes.
So, from the above definition, the line intersects the x-axis at +1 and intersects the y-axis at -2.

Thus, the required x-intercept and y-intercept of the given line in the graph are 1 and -2 respectively.

Learn more about intercept here:
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Answer:

D) 132.67 (this seems to be the closest to the answer, I hope it helps)

Step-by-step explanation:

First, have the area of circle formula: A = π r²

Then, you need to find the radius to be able to complete the area formula. So, since you have the circumference, you will need to use it to find the radius:

C = 2 π r

40.82 = 2 π r

20.41 = π r

r = 6.496704777 . . . Do not round! Rounding will not give an exact answer!

Now that you have the radius, plug in:

A = π r²

   = π (6.49 . . .)²

   = π  (42.20717296 . . .) Do not round! Rounding will not be exact!

   = 132.5977445 . . .

   ≈ 132.6

Answer:

y=-3x+5

bring (4,-7) in other three lines

you will know that it is unreasonable that

-7=-14

-7=-17

-7=14

The equation for the line perpendicular to the line represented by the equation  [tex]y= \ \frac{1}{3} x-2[/tex]  that passes through the point [tex](4,-7)[/tex] will be  [tex]y=-3x+5[/tex].

Equation for the perpendicular line, the perpendicular lines have opposite-reciprocal slopes.

Now,

The equation of a perpendicular line must have a slope that is the negative reciprocal of the original slope.

Equation of a perpendicular line   [tex]y=mx-b[/tex]

Here, [tex]m=[/tex] slope

So,

We have

     [tex]y= \ \frac{1}{3} x-2[/tex]  

Here,

[tex]m = \frac{1}{3}[/tex]

As mentioned above, we have to find the slope of perpendicular,

i.e.

 (slope of perpendicular)  [tex]m[/tex] [tex]=-3[/tex]      

So,

     [tex]y=mx-2[/tex]

[tex]y=(-3)x-b[/tex]

We have

Point [tex](4,-7)[/tex] through which line passes. i.e.

[tex]x=4[/tex]

[tex]y=(-7)[/tex]

Therefore,

    [tex]-7=(-3)*4-b[/tex]

⇒  [tex]b=7-12[/tex]

    [tex]b=(-5)[/tex]

So, Equation of a perpendicular line,

 [tex]y=-3x+5[/tex]

So, Equation of a perpendicular line,  [tex]y=-3x+5[/tex] which is derived from  [tex]y=mx-b[/tex] .

Hence, we can say that the equation for the line perpendicular to the line represented by the equation  [tex]y= \ \frac{1}{3} x-2[/tex]  that passes through the point [tex](4,-7)[/tex] will be  [tex]y=-3x+5[/tex].

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Answer:

try 130.4, I got my answer by subtracting 47.6 with 180. How'd I get 180? the angles are obtuse so that means it'll add up to 180. Thus the answer is 130.4

Answer:

DNE

Step-by-step explanation:

If x and y may be any real number, there is no minimum value for C. It can approach negative infinity.

If C is a constant, and the domain of x is all real numbers, there is no minimum for y. It can approach negative infinity.

We're not sure what you want or what restrictions may exist. The given relation does not suggest any minimum. We'd have to say it Does Not Exist

Hello there,

Use the first constraint to isolate y :

[tex]9x+2y\geq 35[/tex]

[tex]y \geq \frac{35-9x}{2}[/tex]

Now use the second one to isolate x :

[tex]x+3y\geq 14[/tex]

[tex]x\geq 14-3y[/tex]

You know that [tex]x\geq 0[/tex] and [tex]y\geq 0[/tex]

So what's the minimum value of x it's 0 ! Same for y !

So substitute x by 0 and y by 0

[tex]y\geq \frac{35}{2} =17.5[/tex]

[tex]x\geq 14[/tex]

So the minimum value of C is :

[tex]C=14+3*17.5[/tex]

[tex]\boxed{C=66.5}[/tex]

Hope it helps !

Photon