Need help ASAP I will mark brainliest

It looks like you have to find the value of the sum,

[tex]C = \displaystyle \frac1{21\times22\times23} + \frac1{22\times23\times24} + \cdots + \frac1{200\times201\times202}[/tex]

so that the n-th term in the sum is

[tex]\dfrac1{(21+(n-1))\times(21+n)\times(21+(n+1))} = \dfrac1{(n+20)(n+21)(n+22)}[/tex]

for 1 ≤ n ≤ 180.

We can then write the sum as

[tex]\displaystyle C = \sum_{n=1}^{180} \frac1{(n+20)(n+21)(n+22)}[/tex]

Break up the summand into partial fractions:

[tex]\dfrac1{(n+20)(n+21)(n+22)} = \dfrac a{n+20} + \dfrac b{n+21} + \dfrac c{n+22}[/tex]

Combine the fractions into one with a common denominator and set the numerators equal to one another:

[tex]1 = a(n+21)(n+22) + b(n+20)(n+22) + c(n+20)(n+21)[/tex]

Expand the right side and collect terms with the same power of n :

[tex]1 = a(n^2+43n+462)+b(n^2+42n+440) + c(n^2+41n + 420) \\\\ 1 = (a+b+c)n^2 + (43a+42b+41c)n + 462a+440b+420c[/tex]

Then

a + b + c = 0

43a + 42b + 41c = 0

462a + 440b + 420c = 1

==>   a = 1/2, b = -1, c = 1/2

Now our sum is

[tex]\displaystyle C = \sum_{n=1}^{180} \left(\frac1{2(n+20)}-\frac1{n+21}+\frac1{2(n+22)}\right)[/tex]

which is a telescoping sum. If we write out the first and last few terms, we have

C = 1/(2×21) - 1/22 + 1/(2×23)

… … + 1/(2×22) - 1/23 + 1/(2×24)

… … + 1/(2×23) - 1/24 + 1/(2×25)

… … + 1/(2×24) - 1/25 + 1/(2×26)

… … + … - … + …

… … + 1/(2×198) - 1/199 + 1/(2×200)

… … + 1/(2×199) - 1/200 + 1/(2×201)

… … + 1/(2×200) - 1/201 + 1/(2×202)

Notice the diagonal pattern of underlined and bolded terms that add up to zero (e.g. 1/(2×23) - 1/23 + 1/(2×23) = 1/23 - 1/23 = 0). So, like a telescope, the sum collapses down to a simple sum of just six terms,

C = 1/(2×21) - 1/22 + 1/(2×22) + 1/(2×201) - 1/201 + 1/(2×202)

which we simplify further to

C = 1/42 - 1/44 - 1/402 + 1/404

C = 1,115/1,042,118 ≈ 0.00106994

111111101010100110

Step-by-step explanation:

es 125

Answer:

2 x ^2 − 2 y^ 2  +  3 x  +  y

Step-by-step explanation:

Answer:

1320 yds

Step-by-step explanation:

1 mile = 1760 yds

3/4 mile * 1760 yds/ 1 mile

1320 yds

Answer:

1 mile = 1720 yard

______ ________

0.75 x

cross multiply and solve for x

1320 yards is the answer

good luck in the future..

Answer:

The alphabets Z, H, S, N and O have rotational symmetry.

-Answer:

4 lbs of 37% mixed   nuts

Step-by-step explanation:

[tex]\frac{\left(17+.37x\right)}{17+x}\:=\:.88[/tex]

x = 4

Answer:

[tex]x=-\frac{11}{8}[/tex]

Step-by-step explanation:

Hi there!

[tex](x - 4) - (x + 7) = 8x[/tex]

Open up the parentheses

[tex]x - 4 - x - 7 = 8x[/tex]

Combine like terms

[tex]x -x - 4 - 7 = 8x\\-4-7=8x\\-11=8x[/tex]

Divide both sides by 8 to isolate [tex]x[/tex]

[tex]-\frac{11}{8}=x[/tex]

I hope this helps!

Step-by-step explanation:

cosx=adjacent/hypotenuse

adj=3, hyp=5

by pythagoras theorem,

opp^2+3^2=5^2

opposite=4

sine=opp/hyp

sinex=4/5 (second quadrant so sin is positive)

The solution is, The value of sin ∅ in quadrant 2 is 4/5.

Trigonometry is the study of the relationships between the angles and the lengths of the sides of triangles

here, we have,

The six trigonometric functions are sin , cos , tan , cosec , sec and cot

Let the angle be θ , such that

sin θ = opposite / hypotenuse

cos θ = adjacent / hypotenuse

tan θ = opposite / adjacent

here, we have,

given that,

cos∅ = - 3/5, in quadrant II,

We have;

adjacent = -3

hypotenuse = 5

Let's find the opposite side, using Pythagorean theorem

5^2 = x^2 + (-3)^2

25 = x^2 + 9

collect like terms

x^2 = 25 - 9

x^2 = 16

x = √ 16

x = 4

We have that

sin ∅ = opposite/hypotenuse

sin ∅ = 4/5

It is important to note that the trigonometric identity 'sine' is positive in quadrant 2

sin ∅ = 4/5

Hence, the value of sin ∅ in quadrant 2 is 4/5

Learn more about trigonometric relations here:

brainly.com/question/863849

#SPJ7

Answer:

X>3

Step-by-step explanation:

-2.5x +5 < -2.5

-2.5x < -2.5-5

-2.5x< -7.5

X> -7.5/-2.5

X>3

Answer:

A, B, C

Step-by-step explanation:

none of the 4 options changes the shape.

but D changes the size.

C is the only one that also maintains the orientation of the triangle - it only shifts its position.

A and B maintain size and shape, but they do change its orientation.

Answer:

Player B.

Step-by-step explanation:

Player A has a mean score of 25.

Let's calculate Player B's mean score and compare it to Player A's.

23 + 27 + 28 + 22 + 25 / 5 = 125 / 5 = 25.

So, Player A and Player B have the same mean score.

This doesn't tell the scout which player is "better", so let's look at the variance.

The other statistic given for Player A is the standard deviation for their points. The given number is 4. Let’s calculate the standard deviation for Player B, and compare it to player A.

Recall that we add up the squares of the difference between each score and the mean, divide it by the total number of data, and square root that. So, the standard deviation for player B is sqrt(2^2 + 2^2 + 3^2 + 3^2 + 0^2 / 5) = sqrt (26/5) = sqrt (5.2) = 2.3.

Excellent. We have player A’s standard deviation, as well as player B’s standard of deviation. Since player B’s standard deviation is less than player A’s, it can be inferred that player B has more consistent results than player A, and the scout should get Player B.

Hope this helps!

Answer:

B IS THE MID POINT

Step-by-step explanation:

If b lies between AC iy means b is de half

therefore a+b+c=ABC which is the straight line

set x=0 to get insights.

at x=0 to the functions are

-2(0-2)²+3 = -5

-2(0+2)²-3 = -11

-2(0-2)²+3 = -5

-2(0-2)²-3 = -11

weird, for some reason option 1 and 3 seem to be the same, maybe that's an accident by the author.

maybe a + was intended inside the parentheses, dunno.

option 1 and 3 seem fine, although I think there is an error in the options. they shouldn't be exactly the same

Answer:

[tex]n=35[/tex]

Step-by-step explanation:

From the question we are told that:

Standard Deviation [tex]\sigma=4min[/tex]

Let

[tex]CI=95\%[/tex]

Since

Significance level [tex]\alpha[/tex]

[tex]\alpha =1-CI[/tex]

[tex]\alpha =1-0.95[/tex]

Therefore

[tex]Z_{\alpha/2}=Z_{0.025[/tex]

[tex]Z_{\alpha/2}}=1.96[/tex]

Generally the equation for Sample size is mathematically given by

[tex]n = (Z_{\alpha/2}* \frac{\sigma}{E})^2[/tex]

[tex]n= \frac{1.96 * 3}{1}^2[/tex]

[tex]n=35[/tex]

Answer:

x = 10.9

Step-by-step explanation:

Since this is a right triangle, we can us trig functions

tan theta = opp / adj

tan 54 = x / 7.9

7.9 tan 54 = x

x=10.87341

Rounding to the nearest tenth

x = 10.9

Answer:

A and B

Step-by-step explanation:

A and B are the correct options

The solution to the continuous linear relation is: (2,-7)

The data on the table can be presented as:

Relation A

[tex](x_1,y_1) = (-8,-5)[/tex]

[tex](x_2,y_2) = (-3,-6)[/tex]

Relation B

[tex](x_1,y_1) = (-8,-15)[/tex]

[tex](x_2,y_2) = (-3,-11)[/tex]

Plot the points of each relation and draw a line through the points (see attachment)

Write out the point of intersection of the two lines.

[tex](x,y) = (2,-7)[/tex]

Hence, the solution to the continuous linear relation is: (2,-7)

Read more at:

https://brainly.com/question/20291958

Answer: b = 1

Step-by-step explanation:

Given

6.8 - 4.2b = 5.6b - 3

Add 4.2b on both sides

6.8 - 4.2b + 4.2b = 5.6b - 3 + 4.2b

6.8 = 9.8b - 3

Add 3 on both sides

6.8 + 3 = 9.8b - 3 + 3

9.8 = 9.8b

Divide 9.8 on both sides

9.8 / 9.8 = 9.8b / 9.8

[tex]\boxed{b=1}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

Answer:

6

Step-by-step explanation:

A=5-x^2+2x

Rewriting

A = -x^2 +2x+5

This is a downward opening parabola so the maximum value is at the vertex

Factor out the negative sign out of the first two terms

A = -(x^2 -2x)  +5

Complete the square

-2/2 = -1   -1^2 = 1

Add 1 inside the parentheses  Remember the negative sign out front so -1(1) is really adding -1  so we need to add 1 outside of the parentheses

A = -(x^2-2x+1) +1  +5

A = -(x-1)^2 +6

This is in vertex form

y = a(x-h)^2 +k  where (h,k) is the vertex

The maximum occurs at x=h and the value is k

The maximum is 6

Answer:

18.8

Step-by-step explanation:

Surface area=2*pi*r*(r+h)=2*pi*1*(3)=18.8

Answer:

8 cm

Step-by-step explanation:

The length of the whole shape is 13. On the right side, it says the length is 5 cm. You use 13-5 to get the missing length.

Answer:

the answer is 8 cm

Step-by-step explanation:

( yx + 4x - 5 )( y + 1 )

.....................................

Answer:

[tex] = { \tt{(0, \: 0)}}[/tex]

Step-by-step explanation:

Let:

[tex]{ \bf{ - x - 2y = 0 - - - (a)}} \\ { \bf{y = - 8x - - - (b)}}[/tex]

Substitute for y in equation (b) to equation (a):

[tex]{ \tt{ - x - 2( - 8x) = 0}} \\ { \tt{ - x + 16x = 0 }} \\ { \tt{x = 0}}[/tex]

Also, y = 0

Answer:

domain) all real numbers

range) all real numbers

Step-by-step explanation:

y=15-9x

there are no illegal values for x that would make the equation invalid so domain is all real numbers

this line is not flat so range is also all real numbers

Answer:

105897 ft²

Step-by-step explanation:

let, r be the radius, so r = 106 ft

Surface area of a hemisphere,

2πr²+πr²

= 2π×106²+π×106²

= 105897 (rounded to the nearest whole number)

Answer: y= 3+x

Step-by-step explanation:

Answer: y = x - 3

First, find two points on the graph:

Substitute in the points to the slope formula [tex]\frac{y_2-y_1}{x_2-x_1}[/tex] to find the slope:

[tex]\frac{y_2-y_1}{x_2-x_1}=\frac{-3-0}{0-3}=\frac{-3}{-3}=1[/tex]

Substitute in a point to the function [tex]y=1x+b[/tex] to find the y-intercept(b):

[tex]-3=1(0)+b\\b=-3[/tex]

Therefore, the function is:

[tex]y=x-3[/tex]

Answer:

11,5,-2

is the answer. I hope it will help you.

Answer:

[tex]\text{C. }21.39\:\mathrm{units^2}[/tex]

Step-by-step explanation:

The area of a triangle with sides [tex]a[/tex] and [tex]b[/tex] and angle [tex]\gamma[/tex] between them is given by [tex]A=\frac{1}{2}ab\sin \gamma[/tex].

Therefore, in the given triangle, we want to find two sides with the angle between them given. In this case, the angle between the two sides 7.39 and 9.75 is marked as [tex]36.43^{\circ}[/tex]. Assign values:

Substituting these values into our area formula, we get:

[tex]A=\frac{1}{2}\cdot 7.39\cdot 9.75\cdot \sin (36.43)^{\circ},\\A=21.3938371858,\\A\approx \boxed{21.39\:\mathrm{units^2}}[/tex]

Answer:

6 yards 4 feet 1 inch

Step-by-step explanation:

First, we have the equation:

4 yards 2 feet 7 inches + 2 yards 1 foot 6 inches

Now, let's add each:

6 yards

3 feet

13 inches

But 13 inches would be 1 foot and 1 inch, so now we have plus 1 foot and replace the inches with just 1 inch:

6 yards

4 feet

1 inch

There you have it!

Happy learning!

--Applepi101

Answer:

7 yds  1 ft 1 inch

Step-by-step explanation:

 4 yards 2 feet 7 inches

+ 2 yards 1 foot 6 inches

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

 6 yards  3 feet  13 inches

13 inches is more than 12 inches (  =1  ft) so subtract 12 inches and add 1 ft

6 yards  3 feet  13 inches

             =1 ft      - 12 inches

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

6 yds   4 ft    1 inches

4 ft is more than  3f which is 1 yd  ( subtract 3 ft and add 1 yd)

6 yds   4 ft    1 inches

+1 yd  - 3ft

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

7 yds  1 ft 1 inch