Answer:
Maximum at (-6,51), or value of f(-6) = 51
Step-by-step explanation:
f(x) = 8*log(x+7)-8*x+3
differentiate with respect to x
f'(x) = 8/(x+7) -8
To find maximum, set f'(x) = 0
f'(x) = 8/(x+7) -8 = 0
solver for x
x= -6
evaluate f(x) at x=-6
f(-6) = 8log(-6+7) - 8(-6) + 3
= 0 +48 +3
= 51
Note: next time please post only in English. This post will soon be deleted.
To the nearest tenth, what is the area of the figure shown in the image? Segment BF is a line of symmetry of the pentagon ABCDE. Use 3.14 for pi. A. 30.3 in.^2 B. 33.0 in.^2 C. 39.3 in.^2 D. 48.3 in.^2 Please include ALL work! <3
Answer:
C, 39.3 in²
Step-by-step explanation:
Lets first find the area of the rectangle part of the house.
To find the area of a rectangle its base × height.
So its 6×4=24 in².
Now lets find the area of the top triangle.
Area for a triangle is (base × height)/2.
The height is 3 inches, because its 7-4. While the base is 6 inches.
(6×3)/2=9 in².
To find the area of the half circle the formula, (piR²)/2.
The radius of the circle is 2 because its half of the diamter which is 4.
(pi2²)/2=6.283 in².
Now we just need to add up the area of every part,
24+9+6.283=39.283in²
Suppose that you begin with 10 grams of magic crystals, and your crystals grow at a
continuous rate of 25% every day (that's why they're magic). How many grams of
crystals will you have after one week (7 days)?!
ANSWER IS BRAINLEIST
Answer:
After 7 days the crystals will be 57.57 grams.
Step-by-step explanation:
In this the continuous exponential growth formula will be used.
y = A e ^rt
Where A = original amount = 10 grams
y is the growth after 7 days
e is Euler's number= 2.719
t is the time in hours , weeks, years etc.= 7 days
r is the rate in decimals = 25% = 0.25
Putting the values in the formula:
y = A e ^rt
y = 10 e ^0.25 (7)
Calculating with the calculator
y = 10* 2.719^1.75
y= 57.57 grams.
After 7 days the crystals will be 57.57 grams.
Answer:
57.55g
Step-by-step explanation:
Use the formula f(t) = aert, where a = 10, r = 0.25, and t = 7. This gives f(7) = 10e(0.25)(7) = 10e1.75 ≈ 10(5.755) ≈ 57.55.
A company will need to replace 35% of their computers this year. If they replaced 140 computers this year, how many computers do they have in total?
Hi
35/100= 140/ X
X = 100*140 /35
X= 14000/35
X= 400
There are 400 computer in the compagny.
The sequence below represents Marisa’s fine at the library for each day that she has an overdue book: $0.50, $0.65, $0.80, $0.95, $1.10, ... Which equation represents Marisa’s library fine as a function of a book that is n days overdue? f(n) = 0.15n f(n) = 0.50n f(n) = 0.15n + 0.35 f(n) = 0.50n + 0.15
Answer:
f(n) = 0.15n + 0.35Step-by-step explanation:
The sequence of the problem above is an arithmetic sequence
For an nth term in an arithmetic sequence
F(n) = a + ( n - 1)d
where a is the first term
n is the number of terms
d is the common difference
To find the equation first find the common difference
0.65 - 0.5 = 0.15 or 0.80 - 0.65 = 0.15
The first term is 0.5
Substitute the values into the above formula
That's
f(n) = 0.5 + (n - 1)0.15
f(n) = 0.5 + 0.15n - 0.15
The final answer is
f(n) = 0.15n + 0.35Hope this helps you
Answer:
The correct option is: f(n) = 0.15n + 0.35Step-by-step explanation:
Took the math test on edge
You want to construct a pool that will hold 3496 ft. of water if the pool is to be 23 feet long and 19 wide how deep will it need to be
Answer:
8 feet deep
Step-by-step explanation:
volume = length x width x depth
3496 = 23 x 19 x d
3496 = 437 x d
divide both sides by 437
d = 8
When conducting a residual analysis, which plot would you look at to determine if the equal variance assumption is satisfied?
a. Scatter plot of Yhat vs. QN X
b. Scatter Plot of Residuals vs QN X
c. Scatter Plot of Residuals vs Yhat
d. Stem-and-Leaf Plot of the Zresiduals
Answer:
C.Scatter Plot of Residuals vs Yhat
Step-by-step explanation:
find the greatest common factor of 108d^2 and 216d
Answer:
Below
Step-by-step explanation:
If d is a positive number then the greatest common factor is 108d.
To get it isolate d and d^2 from the numbers.
108 divides 216. (216 = 2×108)
Then the greatest common factor of 216 and 108 is 108.
For d^2 and d we will follow the same strategy
d divides d^2 (d^2 = d*d)
Then the greatest common factor of them is d.
So the greatest common factor will be 108d if and only if d is positive. If not then 108 is the answer
Answer:
[tex]\boxed{108d}[/tex]
Step-by-step explanation:
Part 1: Find GCF of variables
The equation gives d ² and d as variables. The GCF rules for variables are:
The variables must have the same base.If one variable is raised to a power and the other is not, the GCF is the variable that does not have a power.If one variable is raised to a power and the other is raised to a power of lesser value, the GCF is the variable with the lesser value power.The GCF for the variables is d.
Part 2: Find GCF of bases (Method #1)
The equation gives 108 and 216 as coefficients. To check for a GCF, use prime factorization trees to find common factors in between the values.
Key: If a number is in bold, it is marked this way because it cannot be divided further AND is a prime number!
Prime Factorization of 108
108 ⇒ 54 & 2
54 ⇒ 27 & 2
27 ⇒ 9 & 3
9 ⇒ 3 & 3
Therefore, the prime factorization of 108 is 2 * 2 * 3 * 3 * 3, or simplified as 2² * 3³.
Prime Factorization of 216
216 ⇒ 108 & 2
108 ⇒ 54 & 2
54 ⇒ 27 & 2
27 ⇒ 9 & 3
9 ⇒ 3 & 3
Therefore, the prime factorization of 216 is 2 * 2 * 2 * 3 * 3 * 3, or simplified as 2³ * 3³.
After completing the prime factorization trees, check for the common factors in between the two values.
The prime factorization of 216 is 2³ * 3³ and the prime factorization of 108 is 2² * 3³. Follow the same rules for GCFs of variables listed above and declare that the common factor is the factor of 108.
Therefore, the greatest common factor (combining both the coefficient and the variable) is [tex]\boxed{108d}[/tex].
Part 3: Find GCF of bases (Method #2)
This is the quicker method of the two. Simply divide the two coefficients and see if the result is 2. If so, the lesser number is immediately the coefficient.
[tex]\frac{216}{108}=2[/tex]
Therefore, the coefficient of the GCF will be 108.
Then, follow the process described for variables to determine that the GCF of the variables is d.
Therefore, the GCF is [tex]\boxed{108d}[/tex].
i will rate you brainliest
Answer:
(3x+11)/ (5x-9)
Step-by-step explanation:
The numerator is what is on the top of the bar in the middle
(3x+11)/ (5x-9)
Answer:
[tex]\large \boxed{\mathrm{Option \ B}}[/tex]
Step-by-step explanation:
The numerator of a fraction is the top section of the fraction.
Find the midpoint of the segment connecting (−1.8, 1.9) and (1.2, 2.7).
Answer:
(-0.3, 2.3)
Step-by-step explanation:
(-1.8+1.2)/2 = -0.3
(1.9+2.7)/2 = 2.3
Answer:
( - 0.3 , 2.3 )Step-by-step explanation:
Let the points be A and B
A ( - 1.8 , 1.9 ) ⇒( x₁ , y₁ )
B ( 1.2 , 2.7 )⇒ ( x₂ , y₂ )
Now, let's find the midpoint:
[tex] \mathsf{ (\frac{x1 + x2}{2} \: , \frac{y1 + y2}{2} )}[/tex]
Plug the values
[tex] \mathsf{ = (\frac{ - 1.8 + 1.2}{2} \: , \frac{1.9 + 2.7}{2} )}[/tex]
Calculate
[tex] \mathsf{ = ( \frac{ - 0.6}{2} \: , \frac{4.6}{2} )}[/tex]
[tex] \mathsf{ = (- 0.3 \:, 2.3)}[/tex]
Hope I helped!
Best regards!
the diameter of Earth's moon is on average 3.8 x 10^8m. Use the formula A=4π² to find the approximate surface area. (Use 3.14 for the value of π)
Answer:
The answer is
[tex]A = 4.53 \times {10}^{17} \: {m}^{2} [/tex]
Step-by-step explanation:
Since the Earth's moon is a sphere
Surface area of a sphere from the question is given by
A = 4πr²
where r is the radius
To find the radius using the diameter we use the formula
radius = diameter / 2
[tex]radius \: = \frac{3.8 \times {10}^{8} }{2} [/tex]
[tex]radius = 1.9 \times {10}^{8} \: m[/tex]
π = 3.14
Substitute these values into the above formula
That's
[tex]A = 4 \times 3.14 \times ({1.9 \times {10}^{8} })^{2} [/tex]
We have the final answer as
[tex]A = 4.53 \times {10}^{17} \: {m}^{2} [/tex]
Hope this helps you
A baseball player has a batting average (probability of getting on base per time at bat) of 0.215. Based on this: What is the probability that they will get on base more than 6 of the next 15 at bats
Answer:
[tex]\mathbf{P(x>6) = 0.0265}[/tex]
Step-by-step explanation:
Given that:
A baseball player has a batting average (probability of getting on base per time at bat) of 0.215
i.e
let x to be the random variable,
consider [tex]x_1 = \left \{ {{1} \atop {0}} \right.[/tex] to be if the baseball player has a batting average or otherwise.
Then
p(x₁ = 1) = 0.125
What is the probability that they will get on base more than 6 of the next 15 at bats
So
[tex]\mathtt{x_i \sim Binomial (n,p)}[/tex]
where; n = 15 and p = 0.125
P(x>6) = P(x ≥ 7)
[tex]P(x>6) = \sum \limits ^{15}_{x=7} ( ^{15 }_x ) \ (0.215)^x \ (1 - 0.215)^{15-x}[/tex]
[tex]P(x>6) = 1 - \sum \limits ^{6}_{x=7} ( ^{15 }_x ) \ (0.215)^x \ (1 - 0.215)^{15-x}[/tex]
[tex]P(x>6) = 1 - \sum \limits ^{6}_{x=0} ( ^{15 }_x ) \ (0.215)^x \ (1 - 0.215)^{15-x}[/tex]
[tex]P(x>6) = 1 -0.9735[/tex]
[tex]\mathbf{P(x>6) = 0.0265}[/tex]
Find the measure of b. A. 63 B. 27 C. 31.5 D. 126
Answer:
126°
Step-by-step explanation:
If that angle is 27, so is angle a.
180-27-27=126
Assume that f(x)=ln(1+x) is the given function and that Pn represents the nth Taylor Polynomial centered at x=0. Find the least integer n for which Pn(0.2) approximates ln(1.2) to within 0.01.
Answer:
the least integer for n is 2
Step-by-step explanation:
We are given;
f(x) = ln(1+x)
centered at x=0
Pn(0.2)
Error < 0.01
We will use the format;
[[Max(f^(n+1) (c))]/(n + 1)!] × 0.2^(n+1) < 0.01
So;
f(x) = ln(1+x)
First derivative: f'(x) = 1/(x + 1) < 0! = 1
2nd derivative: f"(x) = -1/(x + 1)² < 1! = 1
3rd derivative: f"'(x) = 2/(x + 1)³ < 2! = 2
4th derivative: f""(x) = -6/(x + 1)⁴ < 3! = 6
This follows that;
Max|f^(n+1) (c)| < n!
Thus, error is;
(n!/(n + 1)!) × 0.2^(n + 1) < 0.01
This gives;
(1/(n + 1)) × 0.2^(n + 1) < 0.01
Let's try n = 1
(1/(1 + 1)) × 0.2^(1 + 1) = 0.02
This is greater than 0.01 and so it will not work.
Let's try n = 2
(1/(2 + 1)) × 0.2^(2 + 1) = 0.00267
This is less than 0.01.
So,the least integer for n is 2
In this exercise we have to use the knowledge of Taylor Polynomial to calculate the requested function, this way we will have;
the least integer for n is 2
The function given in this exercise corresponds to:
[tex]f(x) = ln(1+x)[/tex]
knowing that the x point will be centered on:
[tex]x=0\\Pn(0,2)\\Error < 0.01[/tex]
By rewriting the equation we have to:
[tex][[Max(f^{(n+1)} (c))]/(n + 1)!] *0.2^{(n+1)} < 0.01[/tex]
So doing the derivatives related to the first function given in the exercise we have to:
[tex]f(x) = ln(1+x)[/tex]
First derivative: [tex]f'(x) = 1/(x + 1) < 0! = 1[/tex] 2nd derivative: [tex]f"(x) = -1/(x + 1)^2 < 1! = 1[/tex] 3rd derivative: [tex]f"'(x) = 2/(x + 1)^3 < 2! = 2[/tex] 4th derivative: [tex]f""(x) = -6/(x + 1)^4 < 3! = 6[/tex]Following this we have to:
[tex]Max|f^{(n+1)} (c)| < n![/tex]
Thus, error is;
[tex](n!/(n + 1)!) * 0.2^{(n + 1)} < 0.01[/tex]
[tex](1/(n + 1))* 0.2^{(n + 1)} < 0.01[/tex]
Let's try n = 1
[tex](1/(1 + 1)) *0.2^{(1 + 1)} = 0.02[/tex]
This is greater than 0.01 and so it will not work. Let's try n = 2
[tex](1/(2 + 1)) * 0.2^{(2 + 1)} = 0.00267[/tex]
This is less than 0.01. So,the least integer for n is 2.
See more about Taylor polynomial at brainly.com/question/23842376
What is the length of the arc on a circle with radius 16 inches intercepted by a 45° angle?
Find the circumference:
Circumference = 2 x PI x radius:
Circumference = 2 x 3.14 x 16 = 100.48 inches.
A full circle is 360 degrees, a 45 degree angle is 1/8 of a full circle.
Arc length = 100.48 / 8 = 12.56 inches.
Please answer this correctly without making mistakes
Answer:
1/2 mi
Step-by-step explanation:
Fairfax to Greenwood is equal to one mile
Now think of it as an equation and substitute 1/2 for fairfax and x for greenwood
1/2 + x = 1
This means that x = 1/2
Because of this from Arcadia to Greenwood it is 1/2 mi
HELP :Write the expression as the
sine or cosine of an angle.
Answer:
sin(4π/21)
Step-by-step explanation:
Step 1: Rearrange expression
sin(π/3)cos(π/7) - cos(π/3)sin(π/7)
Step 2: Use sin(A ± B)
sin(π/3 - π/7)
Step 3: Evaluate
sin(4π/21)
And we have our answer!
Which equation is represented by the graph shown in the image? A. y + 2= x B. y + 1= x C. y - 1= x D. y - 2= x Please show ALL work! <3
Answer:
A. y + 2= x
Step-by-step explanation:
Which equation is represented by the graph shown in the image?
A. y + 2= x
B. y + 1= x
C. y - 1= x
D. y - 2= x
Please show ALL work! <3
The graph shown has a slope of +1 and a y intercept of -2.
All given answer choices have a slope of +1, so that's not the problem.
We need one that has a y-intercept of -2, or the equation should be
y = x-2, or equivalently y+2 = x
which corresponds to answer choice A.
The efficiency for a steel specimen immersed in a phosphating tank is the weight of the phosphate coating divided by the metal loss (both in mg/ft2). An article gave the accompanying data on tank temperature (x) and efficiency ratio (y).
Temp. 174 176 177 178 178 179 180 181
Ratio 0.86 1.31 1.42 1.01 1.15 1.02 1.00 1.74
Temp. 184 184 184 184 184 185 185 186
Ratio 1.43 1.70 1.57 2.13 2.25 0.76 1.37 0.94
Temp. 186 186 186 188 188 189 190 192
Ratio 1.85 2.02 2.64 1.53 2.48 2.90 1.79 3.16
(a) Determine the equation of the estimated regression line. (Round all numerical values to five decimal places.)
y =
(b) Calculate a point estimate for true average efficiency ratio when tank temperature is 186. (Round your answer to four decimal places.)
(c) Calculate the values of the residuals from the least squares line for the four observations for which temperature is 186. (Round your answers to four decimal places.)
(186, 0.94)
(186, 1.85)
(186, 2.02)
(186, 2.64)
(d) What proportion of the observed variation in efficiency ratio can be attributed to the simple linear regression relationship between the two variables? (Round your answer to four decimal places.)
Answer:
Kindly check explanation
Step-by-step explanation:
Given the data:
Temp. 174 176 177 178 178 179 180 181
Ratio 0.86 1.31 1.42 1.01 1.15 1.02 1.00 1.74
Temp. 184 184 184 184 184 185 185 186
Ratio 1.43 1.70 1.57 2.13 2.25 0.76 1.37 0.94
Temp. 186 186 186 188 188 189 190 192
Ratio 1.85 2.02 2.64 1.53 2.48 2.90 1.79 3.16
A)
Using the online linear regression calculator, the lie of best fit which models the data above is :
ŷ = 0.09386X - 15.55523
Where ;
X = independent variable
ŷ = predicted or dependent variable
- 15.55523 = intercept
0.09386 = gradient / slope
B)
Point estimate when tank temperature is 186
ŷ = 0.09386(186) - 15.55523
ŷ = 17.45796 - 15.55523
ŷ = 1.90273
C)
Residual error (y - ŷ), ŷ = 1.90273 when x = 186
(0.94 - 1.90273) = −0.96273
(1.85 - 1.90273) = −0.05273
(2.02 - 1.90273) = 0.11727
(2.64 - 1.90273) = 0.73727
D)
To determine the proportion of observed variation in efficiency ratio, we find the Coefficient of determination R^2, which can be found using the online Coefficient of determination calculator : the r^2 value obtained is 0.4433.
A study was conducted to determine whether magnets were effective in treating pain. The values represent measurements of pain using the visual analog scale. Assume that both samples are independent simple random samples from populations having normal distributions. Use a significance level to test the claim that those given a sham treatment have pain reductions that vary more than the pain reductions for those treated with magnets.
n xbar s
Sham 20 0.41 1.26
Magnet 20 0.46 0.93
Answer and Step-by-step explanation: The null and alternative hypothesis for this test are:
[tex]H_{0}: s_{1}^{2} = s_{2}^{2}[/tex]
[tex]H_{a}: s_{1}^{2} > s_{2}^{2}[/tex]
To test it, use F-test statistics and compare variances of each treatment.
Calculate F-value:
[tex]F=\frac{s^{2}_{1}}{s^{2}_{2}}[/tex]
[tex]F=\frac{1.26^{2}}{0.93^{2}}[/tex]
[tex]F=\frac{1.5876}{0.8649}[/tex]
F = 1.8356
The critical value of F is given by a F-distribution table with:
degree of freedom (row): 20 - 1 = 19
degree of freedom (column): 20 - 1 = 19
And a significance level: α = 0.05
[tex]F_{critical}[/tex] = 2.2341
Comparing both values of F:
1.856 < 2.2341
i.e. F-value calculated is less than F-value of the table.
Therefore, failed to reject [tex]H_{0}[/tex], meaning there is no sufficient data to support the claim that sham treatment have pain reductions which vary more than for those using magnets treatment.
Is 1.45 times 10 to the -7 power a scientific notation
Answer:
Yes.
It is 1.45 x 10^-7 or 0.000000145
Hope it helps!
Answer:
It is 1.45 x 10^-7 or 0.000000145
Step-by-step explanation:
Urgent!!! Please simplify
Answer:
The answer is
3x² - 2x³Step-by-step explanation:
First factor (x+1)² out of the expression
That's
[tex] \frac{ ({x + 1})^{2} (6 \cos( \frac{\pi}{3} )) {x}^{2} - {x}^{3} \times 2 \sin( \frac{\pi}{2} ) }{ ({x + 1})^{2} } [/tex]
Reduce the expression by (x + 1)²
We have
[tex]6 \cos( \frac{\pi}{3} ) \times {x}^{2} - {x}^{3} \times 2 \sin( \frac{\pi}{2} ) [/tex]
Using trigonometric values table
[tex] \cos( \frac{\pi}{3} ) = \frac{1}{2} [/tex]
[tex] \sin( \frac{\pi}{2} ) = 1[/tex]
So we have
[tex]6 \times \frac{1}{2} \times {x}^{2} - {x}^{3} \times 2 \times 1[/tex]
Simplify
We have the final answer as
[tex] {3x}^{2} - 2 {x}^{3} [/tex]
Hope this helps you
Choose the correct ray whose endpoint is B.
Answer:
The second option.
Step-by-step explanation:
The first option consists of a line that extends at both opposite sides to infinity, with no precise end.
The third option is a ray that has an endpoint of A, and extends to infinity towards B.
The fourth option is a line segment. It has two endpoints, B and A.
The second portion is a ray that has an endpoint B, and extends towards A in one direction, to infinity.
The answer is the 2nd option.
The dance team is selling headbands to raise
money for dance team jackets. They need
to sell 1,260 headbands. The headbands must
be divided equally among the three coaches.
Each coach is in charge of 10 dancers. If all
the headbands must be sold, how many
headbands will each dancer on the team
need to sell?
Answer:
42 headbands per dancer
Step-by-step explanation:
Selling 1260 headband
Divide by the three coaches
1260/3
420 per coach
Divide by each dancer under a coach
420/10 = 42
Each dancer must sell 42 headbands
Is -5/6 Real, Rational, Irrational, Integer, Whole, or real number?
Answer:
Rational
Step-by-step explanation:
Rational number consists of
Whole NumbersNatural NumbersIntegersNegative NumbersFractionsDecimals-5/6 is a Fraction and we can also simply it to a Decimal.
Hope this helps ;) ❤❤❤
for each of the following express the first quantity as a percentage of the second quantity 1 year ' 4 month
Answer:
300%
Step-by-step explanation:
1 year = 12 months
percent = part/whole * 100%
percent = 12/4 * 100% = 300%
Answer:
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Two math classes took the same quiz. The scores of 10 randomly selected students from each class are listed below. • Sample of Class A: 75, 80, 60, 90, 85, 80, 70, 90, 70, 65 • Sample of Class B: 95, 90, 85, 90, 100, 75, 90, 85, 90, 85 Based on the medians of the scores for each class, what inference would you make about the quiz scores of all the students in Class A compared to all the students in Class B? Explain your reasoning to justify your answer.
Answer:
Step-by-step explanation:
First you have to find the medians which is when you put the numbers in number order and find the one in the middle.
Class A: 60,65,70,70,75,80,80,85,90,90
=77.5
Class B: 75,85,85,85,90,90,90,90,95,100
=90
That the class B is more advanced, and they probably studied.
You roll two fair dice, a green one and a red one. (a) What is the probability of getting a sum of 6? (Enter your answer as a fraction.) (b) What is the probability of getting a sum of 10? (Enter your answer as a fraction.) (c) What is the probability of getting a sum of 6 or 10? (Enter your answer as a fraction.) Are these outcomes mutually exclusive? Yes No
Answer:
5/36 ; 1/12 ; 2/9 ; yes
Step-by-step explanation:
Given the following :
Roll of two fair dice : green and red
Probability = (number of required outcomes / number of total possible outcomes)
(a) What is the probability of getting a sum of 6?
Number of required outcomes = 5
P(sum of 6) = 5/36
b.) What is the probability of getting a sum of 10?
Number of required outcomes = 3
P(sum of 10) = 3 / 36 = 1/12
c.) What is the probability of getting a sum of 6 or 10?
P(getting a sum of 6) + P(getting a sum of 10)
(5/36) + (1/12) = (5 + 3) / 36
= 8/36 = 2/9
The events are mutually exclusive because each event cannot occur at the same time.
The height (in centimeters) of a candle is a linear function of the amount of time (in hours) it has been burning. When graphed, the function gives a line with a slope of −0.4. See the figure below. Suppose that the height of the candle after 11 hours is 16.6 centimeters. What was the height of the candle after 6 hours?
Answer:
height of the candle after 6 hours= 18.6 centimeters
Step-by-step explanation:
the function gives a line with a slope of −0.4.
the height of the candle after 11 hours is 16.6 centimeters.
after 6 hours, the height will be
But slope= y2-y1/x2-x1
Y2 is the unknown
Y1 = 16.6
X1= 11 hours
X2= 6 hours
y2-y1/x2-x1= -0.4
(Y2-16.6)/(6-11)= -0.4
(Y2-16.6)/(-5)= -0.4
(Y2-16.6)= -5( -0.4)
(Y2-16.6)= 2
Y2 = 2+16.6
Y2 = 18.6 centimeters
height of the candle after 6 hours= 18.6 centimeters
A professor at a local community college noted that the grades of his students were normally distributed with a mean of 74 and standard deviation of 10. The professor has informed us that 6.3 percent of his students received A's while only 2.5 percent of his students failed the course and received F's.
a. What is the minimum score needed to make an A?
b. What is the maximum score among those who received an F?
c. If there were 5 students who did not pass the course, how many students took the course?
Answer:
a) z (score) 1,53
b) z ( score) - 1,96
c) 200 students
Step-by-step explanation:
Normal Distribution N ( 74;10)
a) From z-table, and for 6,3 % ( 0,063 ) we find the z (score) 1,53
Note : 6,3 % or 0,063 is the area under the curve, the minimum score neded to get A
b) To fail 2,5 % ( 0,025 ) from z-table get - 1,96
c) If the group of student who did not pass the course (5) correspond to 2,5 % then by simple rule of three
5 2,5
x ? 100
x = 500/2,5
x = 200
Find the Taylor series for f(x) centered at the given value of a. [Assume that f has a power series expansion. Do not show that Rn(x) → 0.] f(x) = 4 cos(x), a = 7π
Answer:
The Taylor series of f(x) around the point a, can be written as:
[tex]f(x) = f(a) + \frac{df}{dx}(a)*(x -a) + (1/2!)\frac{d^2f}{dx^2}(a)*(x - a)^2 + .....[/tex]
Here we have:
f(x) = 4*cos(x)
a = 7*pi
then, let's calculate each part:
f(a) = 4*cos(7*pi) = -4
df/dx = -4*sin(x)
(df/dx)(a) = -4*sin(7*pi) = 0
(d^2f)/(dx^2) = -4*cos(x)
(d^2f)/(dx^2)(a) = -4*cos(7*pi) = 4
Here we already can see two things:
the odd derivatives will have a sin(x) function that is zero when evaluated in x = 7*pi, and we also can see that the sign will alternate between consecutive terms.
so we only will work with the even powers of the series:
f(x) = -4 + (1/2!)*4*(x - 7*pi)^2 - (1/4!)*4*(x - 7*pi)^4 + ....
So we can write it as:
f(x) = ∑fₙ
Such that the n-th term can written as:
[tex]fn = (-1)^{2n + 1}*4*(x - 7*pi)^{2n}[/tex]
In this exercise we must calculate the Taylor series for the given function in this way;
[tex]f_n= (-1)^{2n+1}(4)(x-7\pi)^{2n}[/tex]
The Taylor series of f(x) around the point a, can be written as:
[tex]f(x) = f(a) + f'(a)(x-a)+\frac{1}{2!} f''(a)(x-a)^2+....[/tex]
Here we have:
[tex]f(x) = 4cos(x)\\a = 7\pi[/tex]
Then, let's calculate each part:
[tex]f(a) = 4cos(7\pi) = -4\\df/dx = -4sin(x)\\(df/dx)(a) = -4sin(7\pi) = 0\\(d^2f)/(dx^2) = -4cos(x)\\(d^2f)/(dx^2)(a) = -4cos(7\pi) = 4[/tex]
Here we already can see two things:
1) The odd derivatives will have a sin(x) function that is zero when evaluated in [tex]x=7\pi[/tex].
2) We also can see that the sign will alternate between consecutive terms.
So we only will work with the even powers of the series:
[tex]f(x) = -4 + (1/2!)*4*(x - 7\pi)^2 - (1/4!)*4*(x - 7\pi)^4 + ....[/tex]
So we can write it as:
[tex]f(x)=\sum f_n[/tex]
Such that the n-th term can written as:
[tex]f_n= (-1)^{2n+1}(4)(x-7\pi)^{2n}[/tex]
See more abour Taylor series at: brainly.com/question/6953942
