It looks like you're trying to evaluate the sum,
[tex]\displaystyle \frac2{4\times7} + \frac2{7\times10} + \frac2{10\times13}+\cdots+\frac2{49\times52}[/tex]
which can be written as
[tex]\displaystyle \sum_{n=1}^{16} \frac2{(3n+1)(3n+4)}[/tex]
Split up the summand into partial fractions:
[tex]\displaystyle \frac2{(3n+1)(3n+4)} = \frac a{3n+1} + \frac b{3n+4} \\\\ \implies 2 = a(3n+4)+b(3n+1) \\\\ \implies 2 = (3a+3b)n+4a+b[/tex]
so that
3a + 3b = 0, or a = -b
4a + b = 2
Solve for a and b :
4a + (-a) = 3a = 2 ==> a = 2/3 ==> b = -2/3
So the sum is
[tex]\displaystyle \frac23 \sum_{n=1}^{16} \left(\frac1{3n+1} - \frac1{3n+4}\right)[/tex]
Write out the first terms and observe that several terms cancel with each other:
2/3 (1/4 - 1/7)
+ 2/3 (1/7 - 1/10)
+ 2/3 (1/10 - 1/13)
+ …
+ 2/3 (1/43 - 1/46)
+ 2/3 (1/46 - 1/49)
+ 2/3 (1/49 - 1/52)
So the sum collapses and simplifies to
[tex]\displaystyle \sum_{n=1}^{16} \frac2{(3n+1)(3n+4)} = \frac23 \left(\frac14 - \frac1{52}\right) = \boxed{\frac2{13}}[/tex]
Help me you guys! it's important!
Answer:
hey mate
surface area of cuboid is 2(lh+bh+hl)
doing for first cuboid
h = 20
l = 6
b = 5
surface area for this cuboid on calculating u get 500 sq.cm
now
second cuboid
h = 12
l = 6
b = 4
calculaye it by formula and u get 288 sq.cm
so total surface area is 500 + 288 = 788 but in this one side is getting counted 2 times which is rectangle with length 6 and 12 so it's area is 12×6 = 72
final ans = 788-72 = 716 cm2
as per me that's ans
brinliest pls
Please help! Will give brainliest to correct answer
We can solve it through proportionality or ratios
2 lamps required to create 4signalsLet lamps required to create 60signals be x
Now
[tex]\\ \sf\longmapsto 2:4=x:60[/tex]
[tex]\\ \sf\longmapsto \dfrac{2}{4}=\dfrac{x}{60}[/tex]
[tex]\\ \sf\longmapsto 4x=60(2)[/tex]
[tex]\\ \sf\longmapsto 4x=120[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{120}{4}[/tex]
[tex]\\ \sf\longmapsto x=30[/tex]
Hi can someone help me with these 3 questions. Thanks :)
Answer:
a) 45° cause tan = sin/cos and sin 45 and cos 45 both give square root 2/2
b) 120°
c) sin = -1/2 = -30° or 330° both are same
Use the trig circle which i have included in the answer to better understand trig angles
hope that answers your question
I want to let you know that each angle has sets of coordinates the left number is cos and right is sin. Ex) sin of 30 is 1/2 and cos of 30 is square root 3/2 In case you dont fully understand dont hesitate to comment.
good luck!!
the ratio of 62 miles to 100 kilometers
9514 1404 393
Answer:
0.99779328
Step-by-step explanation:
The exact conversion factor is ...
1 mi = 1.609344
Then 62 miles is 62×1.609344 km = 99.779328 km.
The ratio of this to 100 km is ...
99.779328/100 = 0.99779328 . . . . ratio of 62 miles to 100 km
A retailer allowed 12% discount and sold a T- shirt at a loss of Rs 16. if he had sold it at 10% discount he would have gained Rs 20.for what price did he purchased the T- shirt.
Answer:
rs. 100
Step-by-step explanation:
in the circle below, ...
Answer:
angle FEG = 66⁰
angle GFH = 90⁰
Two solid spheres have surface areas of 1441 cm? and 2567 cm² respectively. They are melted and recast to form a larger sphere. Find the surface area of the larger sphere in square centimetres.
Surface area of small sphere = 1441cm^2
Surface area of bigger sphere = 2567cm^2
Surface area of largest sphere = 1441 + 2567
= 4008cm²
Must click thanks and mark brainliest
−30=5(x+1)
what is x?
[tex]\\ \rm\Rrightarrow -30=5(x+1)[/tex]
[tex]\\ \rm\Rrightarrow -30=5x+5[/tex]
[tex]\\ \rm\Rrightarrow 5x=-30-5[/tex]
[tex]\\ \rm\Rrightarrow 5x=-35[/tex]
[tex]\\ \rm\Rrightarrow x=\dfrac{-35}{-5}[/tex]
[tex]\\ \rm\Rrightarrow x=7[/tex]
Answer:
x = -7
Step-by-step explanation:
-30 = 5 (x -1 )
5 ( x + 1 ) =-30
5 (x + 1 ) = - 30
5 5
x + 1 = -6
x + 1 -1 = -6 -1
x = - 7
find the area of abc
6m 20m 60m
Answer:
The area of ABC is 60m sq.
Step-by-step explanation:
Area of triangle = 1/2×base×height
so, Area=1/2×20×6
Area= 60m sq.
21. Andre grew a plant for a science experiment. At the end of his
experiment, the plant was 100.8 centimeters tall. Andre calculated
that the plant grew an average of 3.6 centimeters per day since
the start of his experiment. How many days did Andre's
experiment last?
Answer:
he answer is 140 minutes to plant 14 saplings.
Step-by-step explanation:
30 divided by 3=10
so it takes 10 minutes to plant one sapling.
10x14=140 so this is how you get your answer. im 99% sure
Answer:
100.8÷3.6=28
he grew the plant for 28 days
trigonometric identities
With 180° < θ < 270°, we know that both cos(θ) < 0 and sin(θ) < 0.
Then from the Pythagorean identity, it follows that
sin²(θ) + cos²(θ) = 1 ==> sin(θ) = -√(1 - cos²(θ))
and so
sin(θ) = -√(1 - (-8/13)²) = -√105/13
Recall the double angle identity for sine:
sin(2θ) = 2 sin(θ) cos(θ) = 2 (-√105/13) (-8/13) = 16√105/169
Find the nth term of the arithmetic
sequence - 1,2,5, ....
A. 3n - 2
B. -2n + 1
C. 2n + 2
D. 3n - 4
Answer:
3n -4
Step-by-step explanation:
We are adding 3 each time
-1+3 =2
2+3 = 5
The formula for an arithmetic sequence is
an = a1+d(n-1) where a1 is the first term and d is the common difference
an = -1+3(n-1)
= -1 +3n -3
= 3n -4
Martha and Bob went running. They started down the path at 3:25 P.M. When they finished running it was 4:30 P.M. How long did the run take?
Answer:
1 hour and 5 minutes, or 65 minutes.
Step-by-step explanation:
Let's suppose 3:25 was 3:30 by rounding up 5 minutes, to make life easier. In one hour, it would be 4:30, which is when Martha and Bob finished running. So we know that between 3:25 and 4:30, they at least ran one hour. Now, since we rounded up 5 minutes, we have to add that too to make our final running time for them, 1 hour and 5 minutes. Hope this helped!
a giraffe can run 32 miles per hour. what is this speed in feet per second?
Answer:
46.9 ft/sec
Step-by-step explanation:
A giraffe can run 32 miles per hour. What is this speed in feet per second? Round your answer to the nearset tenth.
Please help!!! 25 points!!
-72 + (-30) + 10 =
-72-30+10.
-72-30=-102
10-102 is also the same as
-102+10
The final answer is -92
Answer:
-92
Step-by-step explanation:
-72 + (-30) + 10 =
-72+ -30
Since they both have the same sign, add and then take the sign
72+30 = 102 and then take the negative sign
-102
-102+10
They have opposite signs, so we subtract and take the sign of the larger
102 -10 = 92
And 102 was negative so take the negative sign
-92
What would the equation, slope, and y-intercept be for this?
Answer:
y=-4x+1
Step-by-step explanation:
Equation: y=mx+b where m = slope and b= y intercept
TO find the slope, find the change in y over the change in x , or just to rise over run
From (-1,5) to (0,1), the y changes by -4 and the x changes by 1.
So the slope will be -4
To find the y intercept, find the point at which the line crosses the y-axis.
In this case, it is at (0, 1), so your y intercept will be 1
Plug all this info back into the equation and you get y=-4x+1
The y-intercept is 1 and that’s it sorry I can’t answer the rest.
(2(2 •10^6)=
What does this equal
Answer:
54
Step-by-step explanation:
3.1 2 6 divided by 2 2 = 2 (6 - 2) = 2 4. Dividing exponents : 3.2 5 6 divided by 5 2 = 5 (6 - 2) = 5 4
อ
Water scarcity is increasing for all of the following reasons except
A. demand is increasing
B. the population of the globe is increasing
C. the amount of freshwater on Earth is decreasing
D. more land is being farmed
Please select the best answer from the choices provided
B
Ο Ο Ο Ο
С
D
Answer:
The Answer is C .............
Answer:
D
Step-by-step explanation:
You could see this both ways but I think this is the best answer because land is not saying the specifics for water
Hope this helps <3
Need more thanks? Comment /hearts
Find the lateral surface area of the
following prism:
5 cm
5 cm
-apothem = 3.44 cm
5 cm
5 cm
10 cm
5 cm
Answer:
250 cm²
Step-by-step explanation:
Lateral area of the prism is,
5×10×5
= 250 cm²
Lateral surface area of the given prism is equals to [tex]250cm^{2}[/tex].
What is lateral surface area?" Lateral surface area is defined as the sum of area of the all the surfaces except top and bottom of the given geometrical shape."
Formula used
Lateral surface area of pentagonal prism [tex]=5ah[/tex]
[tex]a=[/tex] edge length of the base
[tex]h=[/tex] height of the prism
According to the question,
For the given pentagonal prism,
Edge length of the base [tex]'a' = 5cm[/tex]
Height of the prism [tex]'h' = 10cm[/tex]
Substitute the value in the formula of lateral surface area we get,
Lateral surface area of pentagonal prism [tex]= 5 \times 5\times 10[/tex]
[tex]= 250cm^{2}[/tex]
Hence, lateral surface area of the given prism is equals to [tex]250cm^{2}[/tex].
Learn more about lateral surface area here
https://brainly.com/question/14001755
#SPJ2
If m={prime integers between 1 and 11}
N={Factor of 12} find
1. MuN
2.MnN
M = {2, 3, 5, 7} (and possibly includes 11 if "between x and y" means to include both x and y)
N = {1, 2, 3, 4, 6, 12}
Then
M U N = {1, 2, 3, 4, 5, 6, 7, 12}
(or possibly {1, 2, 3, 4, 5, 6, 7, 11, 12})
M ∩ N = {2, 3}
how many solutions in 3(6x-2) = 2(9x-3)
Answer:
Infinite solutions
Step-by-step explanation:
Distribute the numbers
3(6x-2) = 18x - 6
2(9x-3) = 18x - 6
18x - 6 = 18 - 6
Since both sides of the equal sign are the same, that means you can plug any number into x, and it will always be a valid answer.
what is the slope in the linear equation y = 2x=1?
Answer:
The slope of the line is 2
Step-by-step explanation:
y=2x+1, compare it to the slope intercept form of a line, y=mx+c, the slope will be 2
Answer:
its 2
comment for more understanding
Good luck
a crate of medicine with a density of 167 pounds per cubic foot will ne shipped from the u.s to israel. what is the crates density in kilometers per cubic meter?
9514 1404 393
Answer:
2675.08 kg/m³
Step-by-step explanation:
[tex]\dfrac{167\text{ lb}}{\text{ft}^3}\times\dfrac{0.45359237\text{ kg}}{1\text{ lb}}\times\left(\dfrac{1\text{ ft}}{0.3048\text{ m}}\right)^3\approx\boxed{2675.08\text{ kg/m$^3$}}[/tex]
please help need nowww will give brainlest to right answer
-144π = -12πk
Answer:
k = 12
Step-by-step explanation:
isolate the variable; divide both sides that dont contain the variable
Answer:
K=12
Step-by-step explanation:
-144π = -12πk
divide by -12π on both sides to find k
-144π / -12π = k
12 = k
f(x) = Square root of quantity x plus seven. ; g(x) = 8x - 11 Find f(g(x)). (1 point)
f(g(x)) = 2 Square root of quantity two x plus one
f(g(x)) = 8 Square root of quantity x plus seven - 11
f(g(x)) = 8 Square root of quantity x plus four
f(g(x)) = 2 Square root of quantity two x minus one
Answer:
2 sqrt(2x-1)
Step-by-step explanation:
f(x) = sqrt(x+7)
g(x) = 8x-11
f(g(x))=
Place g(x) in for x in the function f(x)
f(g(x)) = sqrt( 8x-11 +7)
= sqrt( 8x -4)
Factor out 4
= sqrt( 4(2x-1)
= 2 sqrt(2x-1)
[tex]\\ \sf\longmapsto f(x)=\sqrt{x+7}[/tex]
[tex]\\ \sf\longmapsto g(x)=8x-11[/tex]
g(x) will be put on the place of x[tex]\\ \sf\longmapsto f(g(x))=\sqrt{8x-11+7}[/tex]
[tex]\\ \sf\longmapsto f(g(x))=\sqrt{8x-4}[/tex]
[tex]\\ \sf\longmapsto f(g(x))=\sqrt{4(2x-1)}[/tex]
[tex]\\ \sf\longmapsto f(g(x))=2\sqrt{2x-1}[/tex]
(x-5)^2 - (x+1)^2+ (x+3)*(x-3)
Step-by-step explanation:
here's the answer to your question
5^-4 over 5^3
simplify
A. 5^7
B. 5^-1
C. 1/5
D. 1/5^7
Answer:
D is the correct answer.
HELP PLS PLS PLS PLS
now that I have your attention help me answer this question:
Team A built 8 sandcastles in 2 hours and Team B built 5 sandcastles in 1 hour. Which team worked at a faster rate?
if you convert it all into one hour, Team B clearly worked at a faster pace.
Answer:
[tex]team \: a \: \\ 8in \: number \: with \: in \: 2 \: hours \\ so \: in \: 1 \: hour \: \frac{8}{2} = 4 \: in \: number \\ \\ team \: b \\ 5 \: in \: 1hour \\ so \: \: team \: b \: work \: in \: fast \\ thank \: you[/tex]
A shipping container is in the shape of a right rectangular prism with a length of 9 feet, a width of 12 feet, and a height of 14.5 feet. The container is completely filled with contents that weigh, on average, 0.83 pounds per cubic foot. What is the weight of the contents in the container, to the nearest pound
Answer:
1,300 lb.
Step-by-step explanation:
V = 9 × 12 × 14.5 = 1566 ft³
1,566 × 0.83 = 1,299.78 ≈ 1,300 lb.
A= 12b1+b2h ; solve for b1
Answer:
b1 = 0, b2 = 0
EXPLICACION
A = 12 b1 + b2 h
A - 12 b1 - b2 h = 0
b2!=0, h = -(12 b1)/b2
