Answers
Answer:
See explanation
Step-by-step explanation:
We are given f(x)=ln(1+x)-x+(1/2)x^2.
We are first ask to differentiate this.
We will need chain rule for first term and power rule for all three terms.
f'(x)=(1+x)'/(1+x)-(1)+(1/2)×2x
f'(x)=(0+1)/(1+x)-(1)+x
f'(x)=1/(1+x)-(1)+x
We are then ask to prove if x is positive then f is positive.
I'm thinking they want us to use the derivative part in our answer.
Let's look at the critical numbers.
f' is undefined at x=-1 and it also makes f undefined.
Let's see if we can find when expression is 0.
1/(1+x)-(1)+x=0
Find common denominator:
1/(1+x)-(1+x)/(1+x)+x(1+x)/(1+x)=0
(1-1-x+x+x^2)/(1+x)=0
A fraction can only be zero when it's numerator is.
Simplify numerator equal 0:
x^2=0
This happens at x=0.
This means the expression,f, is increasing or decreasing after x=0. Let's found out what's happening there. f'(1)=1/(1+1)-(1)+1=1/2 which means after x=0, f is increasing since f'>0 after x=0.
So we should see increasing values of f when we up the value for x after 0.
Plugging in 0 gives: f(0)=ln(1+0)-0+(1/2)0^2=0.
So any value f, after this x=0, should be higher than 0 since f(0)=0 and f' told us f in increasing after x equals 0.
Related Questions
20 students were asked “How many pets do you have in your household?” and the following data was collected:
2 1 0 3 1 2 1 3 4 0
0 2 2 0 1 1 0 1 0 1
Select the type of the data ?
CHOOSE ONE PLEASE HELP
Discrete
Continuous
Categorical
Qualitative
Answers
Answer:
Discrete
Discrete data represent items that can be counted; they take on possible values that can be listed out. The list of possible values may be fixed (also called finite); or it may go from 0, 1, 2, on to infinity (making it countably infinite).
What is the slope of the points (-2,7) and (2,-5)?
4
-3
-12
3
Answers
Answer:
-3
Step-by-step explanation:
Slope is equal to (-5-7)/(2-(-2)=-12/4=-3
What steps are included in the construction of a perpendicular line through a point on a line
Answers
Answer:
A perpendicular line from a given point
Place your compass on the given point (point P).
From each arc on the line, draw another arc on the opposite side of the line from the given point (P).
Use your ruler to join the given point (P) to the point where the arcs intersect (Q).
Answer:
get the slope of original line
take the inverse of the slope and multiply by -1 (2/3 becomes - 3/2)
y = -b/a x + b
plug on y & x using the given point
calculate the "B"
go back to the y = -b/ax + calculated "B"
that is your answer
Step-by-step explanation:
Martina got a prepaid debit card with $20 on it. For her first purchase with the card, she bought some bulk ribbon at a craft store. The price of the ribbon was 19 cents per yard. If after that purchase there was $15.63 left on the card, how many yards of ribbon did Martina buy?
Answers
Phone card = $20
You need to minus 17.92 from 20 = $2.08
$2.08 / 0.13 = how many minutes
= 16
find the value of the trigonometric ratio
Answers
Answer:
15/17
Step-by-step explanation:
sinA = CB/CA =15/17
Answer:
15/17Step-by-step explanation:
sine = opposite / hypotenusesin A = BC/ACsin A = 15/17Kendall wants to estimate the percentage of vegetarians who are also vegan. She surveys 150 vegetarians and finds that 45 are vegan. Find the margin of error for the confidence interval for the population proportion with a 95% confidence level.
Answers
Answer:
0.0733364
Step-by-step explanation:
Given :
Number of vegans = x ;
Sample size, n = 150
Zα/2 ; Zcritical at 95% = 1.96
p = x / n = 45 / 150 = 0.3
Margin of Error :
Zcritical * √(p(1 - p) / n)
1.96 * √(0.3(1 - 0.3) / 150)
Margin of Error :
1.96 * √(0.3 * 0.7) / 150)
1.96 * √0.0014
Margin of Error = 0.0733364
2 hundreds equal how many tens?
Lets see if ya'll know the answer cause i do
Answers
Answer:
200 is equal to 20 tens I guess lol
Answer:
20 tens
Step-by-step explanation:
200÷10=20 groups of ten
what should be added to 7777 to get 4999
Answers
An automobile went 84 miles on 6.5 gallons of gasoline. At this rate, how many gallons would be needed to travel 126 miles
Answers
Answer:
10 gallons
Step-by-step explanation:
84 ÷ 6.5 =12.9(The unit rate.)
Seeing as one gallon can get you 12.9 miles;
126÷12.9=9.7
So the answers 9.7 gallons, but if you need to round, then 10 to get a whole number.
Answer:
9.75
Step-by-step explanation:
We can write a ratio to solve
84 miles 126 miles
-------------- = -------------------
6.5 gallons x gallons
Using cross products
84 x = 6.5 * 126
84x=819
84x/84 = 819/84
x = 9.75
Working at home: According to the U.S Census Bureau, 41% of men who worked at home were college graduates. In a sample of 506 women who worked at home, 166 were college graduates. Part: 0 / 30 of 3 Parts Complete Part 1 of 3 (a) Find a point estimate for the proportion of college graduates among women who work at home. Round the answer to at least three decimal places. The point estimate for the proportion of college graduates among women who work at home is .
Answers
Solution :
a). The point estimate of proportion of college graduates among women who work at home,
[tex]$\hat p =\frac{166}{506}$[/tex]
= 0.3281
99.5% confidence interval
[tex]$=\left( \hat p \pm Z_{0.005/2} \sqrt{\frac{\hat p (1- \hat p)}{n}} \right)$[/tex]
[tex]$=\left( 0.3281 \pm 2.81 \sqrt{\frac{0.3281 \times (1- 0.3281)}{506}} \right)$[/tex]
[tex]$=(0.3281 \pm 0.0586)$[/tex]
[tex]$=(0.2695, 0.3867)$[/tex]
Draw a graph of direct proportion, expressed by the formula: y=3x
Answers
Answer.
ANSWER
.......
The sample size needed to estimate the difference between two population proportions to within a margin of error E with a significance level of ? can be found as follows. In the expression
E=z?p1(1?p1)n1+p2(1?p2)n2?????????????????????????
we replace both n1 and n2 by n (assuming that both samples have the same size) and replace each of p1, and p2, by 0.5 (because their values are not known). Then we solve for n, and get
n=(z?)22E2.
Finally, increase the value of n to the next larger integer number.
Use the above formula and Table C to find the size of each sample needed to estimate the difference between the proportions of boys and girls under 10 years old who are afraid of spiders. Assume that we want a 99% confidence level and that the error is smaller than 0.07.
n=______.
Answers
Answer:
n= (z)22E2
n=10× 99%÷ 0.07
if 2x + 1=7 what is the value of x
Answers
Answer:
x=3
Step-by-step explanation:
2x+1=7
2x=7-1
2x=6
x=6/2
x=3
Answer:
Solution,
2x + 1=7
or 2x = 7 - 1
or, 2x= 6
or, x = 6
2
or, x = 3
.:. x = 3
for any Integer 'a',a ÷ 0 is _______
give me answer
Answers
Answer:
undefined, invalid
and for a limit expression like a/x, x->0 we also say this is infinite.
help with math it would help with summer school
Answers
Answer:
[tex]A). \ \ \frac{(72\pi + 9\pi )}{4} \ in^2[/tex]
Step-by-step explanation:
Given;
radius of the circle, r = 9 inches
the part of the circle cut out = one-forth of the complete circle
the angle of the sector cut out θ= ¹/₄ x 360 = 90⁰
Area of the complete circle = πr² = π x 9² = 81π in²
Area of the sector cut out = [tex]= \frac{\theta }{360} \pi r^2 = \frac{90}{360} \pi (9^2) = \frac{1}{4} \times 81\pi = \frac{81 \pi}{4} = \frac{(72\pi + 9\pi)}{4} \ in^2[/tex]
Therefore, the only correct option is A. [tex]\frac{(72\pi + 9\pi )}{4} \ in^2[/tex]
P over 8 4
The solution is ___.
Answers
9514 1404 393
Answer:
1680
Step-by-step explanation:
nPk = n!/(n-k)!
8P4 = 8!/(8-4)! = 8·7·6·5 = 1680
According to an independent research, a point estimate of the proportion of U.S. consumers of black tea is p = 0.76. Calculate the sample size needed to be 95% confident that the error in estimating the true value of p is less than 0.015? Use the z-value rounded to two decimal places to obtain the answer. 4072.69
Answers
Answer:
The sample size needed is 3115.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
Point estimate:
[tex]\pi = 0.76[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
Calculate the sample size needed to be 95% confident that the error in estimating the true value of p is less than 0.015?
This is n for which M = 0.015. So
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.015 = 1.96\sqrt{\frac{0.76*0.24}{n}}[/tex]
[tex]0.015\sqrt{n} = 1.96\sqrt{0.76*0.24}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.76*0.24}}{0.015}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96\sqrt{0.76*0.24}}{0.015})^2[/tex]
[tex]n = 3114.26[/tex]
Rounding up:
The sample size needed is 3115.
Identify the terminal point for a 45° angle in a unit circle.
O A (231)
O B.
O c.
V2 72
Answers
Answer:
D
Step-by-step explanation:
x- coordinate = cos45° = [tex]\frac{1}{\sqrt{2} }[/tex] = [tex]\frac{\sqrt{2} }{2}[/tex]
y- coordinate = sin45° = [tex]\frac{1}{\sqrt{2} }[/tex] = [tex]\frac{\sqrt{2} }{2}[/tex]
That is ( [tex]\frac{\sqrt{2} }{2}[/tex] , [tex]\frac{\sqrt{2} }{2}[/tex] ) → D
The critical value of F for an upper tail test at a 0.05 significance level when there is a sample size of 21 for the sample with the smaller variance and there is a sample size of 9 for the sample with the larger sample variance is _____. a. 2.94 b. 2.45 c. 2.10 d. 2.37
Answers
Answer:
2.45
Step-by-step explanation:
Given that :
α = 0.05
Larger sample variance= numerator, sample size = 9
Smaller sample variance = denominator, sample size = 21
Hence,
DFnumerator = n - 1 = 9 - 1 = 8
DFdenominator = n - 1 = 21 - 1 = 20
Critical value for upper tail test using the F distribution table at α = 0.05 ; DFnumerator on horizontal ; Df denominator as vertical ;
F critical = 2.447
F critical = 2.45
what is 127/14 simplified?
Answers
Answer:
9 1/14
Step-by-step explanation:
127 ÷14
127 divided by 14 equals
9 with a remainder of 1
The weights of items produced by a company are normally distributed with a mean of 4.5 ounces and a standard deviation of 0.3 ounce. a. What is the probability that a randomly selected item from the production will weigh at least 4.14 ounces? b. What percentage of the items weighs between 4.8 and 5.04 ounces? c. Determine the minimum weight of the heaviest 5% of all items produced. d. If 27,875 items of the entire production weigh at least 5.01 ounces, how many items have been produced?
Answers
Answer:
The right solution is:
(a) 0.8849
(b) 12.28%
(c) 4.9935
(d) 28004
Step-by-step explanation:
Given:
Mean,
= 4.5
Standard deviation,
= 0.3
(a)
P(x > 4.14)
As we know,
⇒ [tex]z = \frac{4.14-4.5}{0.3}[/tex]
[tex]=-1.20[/tex]
then,
⇒ [tex]P(z>-1.20) = P(z<1.20)[/tex]
[tex]=0.8849[/tex]
(b)
P(4.8 < x < 5.04)
= [tex]P(\frac{4.8-4.5}{0.3} < \frac{x-\mu}{\sigma} < \frac{5.04-4.5}{0.3} )[/tex]
= [tex]P(1<z<1.80)[/tex]
= [tex]P(z<1.80)-P(z<1)[/tex]
= [tex]0.9641 -0.8413[/tex]
= [tex]0.1228[/tex]
or,
= [tex]12.28[/tex] (%)
(c)
P(x > x) = 0.05
z value will be,
= 1.645
⇒ [tex]1.645 = \frac{x - 4.5}{0.3}[/tex]
[tex]x = 4.9935[/tex]
(d)
P(x < 5.01)
⇒ [tex]z = \frac{x- \mu}{\sigma}[/tex]
[tex]=\frac{5.01-4.5}{0.3}[/tex]
[tex]=1.7[/tex]
P(z < 1.70) = 0.9554
⇒ [tex]n = \frac{27875}{0.9954}[/tex]
[tex]=28004[/tex]
The picture shows the graph of the movement of a pedestrian (B) and a bicyclist (A). Using the graph, answer the following questions: How many times is the distance covered by the bicyclist for 1 hour greater than the distance covered by the pedestrian for the same amount of time
Answers
Answer:
15km
Step-by-step explanation:
hope it is well understood
find two ordered pairs for x-4y=2
Answers
Answer:
x-4y=2 can be written as y=(x-2)/4
(2,0) when x=2, y=0 and (6,1) when x=6, y=1
Write a quadratic equation in standard form that has two solutions, 9 and -2
(the leading coefficient must be 1.)
Answers
x^2 + 2x -9x -18 = 0
x^2 - 7x - 18 = 0
Pam’s eye-level height is 324 ft above sea level, and Adam’s eye-level height is 400 ft above sea level. How much farther can Adam see to the horizon? Use the formula d = StartRoot StartFraction 3 h Over 2 EndFraction EndRoot, with d being the distance they can see in miles and h being their eye-level height in feet.
1 mi
StartRoot 6 EndRoot mi
19 mi
19 StartRoot 6 EndRoot mi
Answers
9514 1404 393
Answer:
(b) √6 mi
Step-by-step explanation:
Putting the given heights into the formula, we find the difference in distances to be ...
Adam' horizon distance = √((3/2)(400)) = 10√6 . . . miles
Pam's horizon distance = √((3/2)(324)) = 9√6 . . . . miles
Then the difference Adam can see is farther than the distance Pam can see by ...
10√6 -9√6 = √6 . . . miles
3. A rectangular sheet of paper is 121/2 cm long and 102/3 cm wide. Find its perimeter .
Answers
Answer:189 cm
Step-by-step explanation:
the area of a perimeter is 2L+2w while l is length and w is width
in this case, 121/2 is the length and 102/3 is the width.
using the formula it should be
121/2 x 2 +102/3 x
= 121 + 68
=189 cm
i hope this helps.
Please if anyone can help me
Answers
how to work this fraction 4/11+5/22+3/44
Answers
Answer:
29/44
Step-by-step explanation:
[tex]\frac{4}{11} +\frac{5}{22} +\frac{3}{44} =\\[/tex]
-find the common denominator
[tex]\frac{4*4}{4*11} + \frac{2*5}{2*22} +\frac{3}{44} =[/tex]
[tex]\frac{16}{44} +\frac{10}{44} +\frac{3}{44} =[/tex]
-add the fractions and solve
[tex]\frac{16+10+3}{44} =[/tex]
[tex]\frac{29}{44}[/tex]
Which of the following statements correctly explains the meaning of the term "95% confidence" in the confidence statement? The interval 52% to 58% is based on a procedure that includes a sample representing 95% of population. The interval 52% to 58% is based on a procedure that includes the true population value 95% of the time. The interval 52% to 58% is based on a procedure that produces a margin of error (of ±3) 95% of the time.
Answers
Answer:
The interval 52% to 58% is based on a procedure that includes the true population value 95% of the time.
Step-by-step explanation:
x% confidence interval:
A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.
95% confidence
We are 95% sure that the interval contains the true mean/proportion, and thus, the correct option is:
The interval 52% to 58% is based on a procedure that includes the true population value 95% of the time.
PLEASE HELPPPPPPPPPPPPPP
Answers
Answer:
False
Step-by-step explanation:
To find the inverse of a function, switch the variables and solve for y.
The inverse of f(n)=-(n+1)^3:
[tex]y=-(n+1)^3[/tex]
[tex]n=-(y+1)^3[/tex]
[tex]\sqrt[3]{n} =-(y+1)[/tex]
[tex]\sqrt[3]{n} =-y-1[/tex]
[tex]\sqrt[3]{n} +1=-y[/tex][tex]-(\sqrt[3]{n} +1)=y[/tex]
[tex]-\sqrt[3]{n} -1=y[/tex]
Answer:
False
Step-by-step explanation:
