Local versus absolute extrema. If you recall from single-variable calculus (calculus I), if a function has only one critical point, and that critical point is a local maximum (or say local minimum), then that critical point is the global/absolute maximum (or say global/absolute minnimum). This fails spectacularly in higher dimensions (and thereís a famous example of a mistake in a mathematical physics paper because this fact was not properly appreciated.) You will compute a simple example in this problem. Let f(x; y) = e 3x + y 3 3yex . (a) Find all critical points for this function; in so doing you will see there is only one. (b) Verify this critical point is a local minimum. (c) Show this is not the absolute minimum by Önding values of f(x; y) that are lower than the value at this critical point. We suggest looking at values f(0; y) for suitably chosen y
Answer:
Step-by-step explanation:
Given that:
a)
[tex]f(x,y) = e^{3x} + y^3 - 3ye^x \\ \\ \implies \dfrac{\partial f}{\partial x} = 0 = 3e^{3x} -3y e^x = 0 \\ \\ e^{2x}= y \\ \\ \\ \implies \dfrac{\partial f}{\partial y } = 0 = 3y^2 -3e^x = 0 \\ \\ y^2 = e^x[/tex]
[tex]\text{Now; to determine the critical point:}[/tex]- [tex]f_x = 0 ; \ \ \ \ \ f_y =0[/tex]
[tex]\implies e^{2x} = y^4 = y \\ \\ \implies y = 0 \& y =1 \\ \\ since y \ne 0 , \ \ y = 1, \ \ x= 0\\\text{Hence, the only possible critical point= }(0,1)[/tex]
b)
[tex]\delta = f_xx, s = f_{xy}, t = f_{yy} \\ \\ . \ \ \ \ \ \ \ \ D = rt-s^2 \\ \\ i) Suppose D >0 ,\ \ \ r> 0 \ \text{then f is minima} \\ \\ ii) Suppose \ D >0 ,\ \ \ r< 0 \ \text{then f is mixima} \\ \\ iii) \text{Suppose D} < 0 \text{, then f is a saddle point} \\ \\ iv) Suppose \ D = 0 \ \ No \ conclusion[/tex]
[tex]Thus \ at (0,1) \\ \\ \delta = f_{xx} = ge^{3x}\implies \delta (0,1) = 6 \\ \\ S = f_{xy} = -3e^x \\ \\ \implies S_{(0,1)} = -3 \\ \\ t = f_{yy} = 6y \\ \\[/tex]
[tex]\implies t_{0,1} = 6[/tex]
[tex]Now; D = rt - s^2 \\ \\ = (6)(6) -(-3)^2[/tex]
[tex]= 36 - 9 \\ \\ = 27 > 0 \\ \\ r>0[/tex]
[tex]\text{Hence, the critical point} \ (0,1) \ \text{appears to be the local minima}[/tex]
c)
[tex]\text{Suppose we chose x = 0 and y = -3.4} \\ \\ \text{Then, we have:} \\ \\ f(0,-3.4) = 1+ (-3.4)^3 + 3(3.4) \\ \\ = -28.104 < -1[/tex]
[tex]\text{However, if f (0,1) = 1 +1 -3 = -1 \\ \\ f(0,-3.4) = -28.104} < -1} \\ \\ \text{This explains that} -1 \text{is not an absolute minimum value of f(x,y)}[/tex]
85.82 rounded to the hundredths place
Answer:
85.80
Step-by-step explanation:
85.82 is closet to 85.80 snice 2 is a low number
How high is the end of the ladder against a building
The following data show the average retirement ages for a random sample of workers in the United States and a random sample of workers in Japan. Perform a hypothesis test using α = 0.05 to determine if the average retirement age in Japan is different from the United States. Calculate the test-statistics (round to 3 decimals - report the absolute value).
Answer:
[tex]t \approx 2.639[/tex]
Step-by-step explanation:
Given
[tex]\begin{array}{ccc}{} & {USA\ 1} & {Japan\ 2} & {\bar x} & {64.6} & {67.5} &{n} & {30} & {30} & {\sigma} & {4.0} & {4.5} \ \end{array}[/tex]
See attachment for data
Required
Determine the test statistic
The test statistic is calculated using:
[tex]t = \frac{\bar x_1 - \bar x_2}{\sqrt{\frac{\sigma_1^2}{n_1} + \frac{\sigma_2^2}{n_2}}}[/tex]
So, we have:
[tex]t = \frac{64.6 - 67.5}{\sqrt{\frac{4.0^2}{30} + \frac{4.5^2}{30}}}[/tex]
[tex]t = \frac{64.6 - 67.5}{\sqrt{\frac{16.00}{30} + \frac{20.25}{30}}}[/tex]
[tex]t = \frac{64.6 - 67.5}{\sqrt{\frac{16.00+20.25}{30}}}[/tex]
[tex]t = \frac{64.6 - 67.5}{\sqrt{\frac{36.25}{30}}}[/tex]
[tex]t = \frac{-2.9}{\sqrt{1.2083}}[/tex]
[tex]t = \frac{-2.9}{1.099}[/tex]
[tex]t \approx -2.639[/tex]
The absolute value is:
[tex]t \approx 2.639[/tex]
2^3=4^p find the value of p
Answer:
Exact form: p= 3/2
Decimal form: p= 1.5
Mixed Number: p=1 [tex]\frac{1}{2}[/tex]
Step-by-step explanation:
Point M is on line segment LN. Given LN=4x, MN= x, and LM=3, determine the numerical length of LN.
Answer:
LN = 4 units
Step-by-step explanation:
Since M is on LN , then
LN = LM + MN , that is
4x = 3 + x ( subtract x from both sides )
3x = 3 ( divide both sides by 3 )
x = 1
Then
LN = 3 + x = 3 + 1 = 4
The required length of the line LN = 4.
Given that,
Point M is on the line segment LN. Given LN=4x, MN= x, and LM=3, to determine the numerical length of LN.
The line is a curve showing the shortest distance between 2 points.
LN = LM + MN
4x = 3 + x
4x - x = 3
3x = 3
x = 3 / 3
x = 1
Length of LN
LN = 4x
= 4 * (1)
= 4
Thus the required length of the line LN = 4.
Learn more about lines here:
brainly.com/question/2696693
#SPJ5
The radius of a circle is 16 cm. Find its area in terms of \piπ
Answer256pi
Step-by-step explanation:
Area=pi*r^2
=pi*16^2
256pi
Vincent began his weekly chores on Saturday morning at 11:20 he worked for 1 hour and 15 minutes with a 10 minute break at what time did Vincent finish his chores
Answer:
12:45
Step-by-step explanation:
Step One: An hour after 11:20 is 12:20, plus 15 minutes is 12: 35.
Step Two: Just add 10 minutes, because it doesn't matter when you add the ten minutes.
what is the remainder when the polynomial f(x) = x³ - x² + 3x - 2, is divided by 2x - 1
Answer:
Equate the divisor to 0
2x-1=0
2×=1
×=1/2
Putting onto the polynomial
f(1/2) = (1/2)³-1/2)²+3(1/2)-2
=-5/8
Josiah earns $8.00 per hour at his job.
Write and solve an inequality that represents how many hours it will take him to earn at least $120.
Answer:
15 hours
so, 8 x y = 120
Step-by-step explanation:
[tex]8\sqrt{120} =[/tex] 15
round off all answer in to two decimal places A=p(1+in) Steven won a portion of the local lottery.the price money is to the value of R18000.he wants to invest the money but does not know which bank to choose. FNB offers Steven 5,6/% for 8 years simple interest per annum, Nedbank offers Steven 6,6% for 6 years simple interest per annum and standard bank offers 7,2% for 5 years simple interest determine each bank future value to help Steven decide which bank he should choose FNB NEDBANK STANDARD BANK
Answer:
FNB bank
Step-by-step explanation:
FNB = 18000 * 0.056* 8 = 8064
Nedbank = 18000*0.066* 6 = 7128
Standard = 18000*0.072*5=6480
FNB is the best choice for Steven
is 2/3 equal to 2/4 ? if not is it greater
Answer:
Equivalent fraction of a given fraction is got by multiplying or dividing its numerator and denominator by the same whole number. For example, if we multiply the numerator and denominator of 2/3 by 4 we get. 2/3 = 2×4 / 3×4 = 8/12 which is an equivalent fraction of 2/3.
Step-by-step explanation:
John buys an item that costs $50.00 is marked 20% off. Sales tax for the item is 8%. What is the final price that John pays, including tax?
Answer:
$43.20
Step-by-step explanation:
20% of $50.00 is $10.00. $50 - $10 is $40. 8% of $40 is $3.20. Since this is tax, you must add it. $40+$3.20 = $43.20
Select the option that best describes the relationship
between the variables on the scatter plot.
35
positive, linear association
30
25
no association
20
15
positive, non-linear association
10
5
negative, linear association
10
12
Activate Windows
Answer:
4th one its negative,linear association
Step-by-step explanation:
The option that best describes the relationship between the variables on the scatter plot is negative, linear association.
What is a negative linear association?Variables have a negative association when the line of best fit is downward sloping. Variables have a linear association when the line of best fit is a straight line. Variables have a positive association when the line of best fit is upward sloping.
To learn more about linear functions, please check: https://brainly.com/question/26434260
John used AABC to write a proof of the Centroid Theorem. He began by drawing medians AK and CL,
intersecting at Z. Next he drew midsegments LM and NP, both parallel to median AK.
Given: AABC with medians AK and CL, and midsegments LM and NP.
2
Prove: Z is located of the distance from each vertex of AABC to the midpoint of the opposite side.
3
Answer:
Hello your question is poorly written attached below is the complete question
answer : attached below
Step-by-step explanation:
To Prove: Z is located 2/3 of the distance from each vertex of ΔABC to the midpoint of the opposite side. we will apply ; property of bisecting a line , equality theorem , transitive property and similarity theorem
Attached below is the proof
help me please!! i’m confused!!
Which is greater 3/5 or 7/10
Answer:
7/10
Step-by-step explanation:
Use the butterfly method:
3/5 7/10
multiply the denominator and numerator to each other sides:
3 * 10 = 30
5 * 7 = 35
35 > 30
35 belongs to 7/10 so:
7/10 is greater
4
Brad goes to bed at 21 25.
He is in bed until 0708 the next day.
Work out the length of time that Brad is in bed.
Answer:
Step-by-step explanation:
You want to have $150,000 in your retirement account when you retire in 30 years. Your retirement account earns 7%
interest. How much do you need to deposit each month to meet your retirement goal?
Round your answer to the nearest cent.
Do NOT include the dollar sign.
Answer: 123.05
Use annuity formula
Answer:
Step-by-step explanation:
Since we're talking about making a deposit of a certain amount every month rather than just one big deposit, we are talking about an annuity. The formula for the value of an annuity is A(t)=d[(1+rn)nt−1](rn) where A(t) is the value of the annuity, d is the amount of each deposit, n is the number of deposits per year, t is the number of years, and r is the rate of interest. In this case we know we want the value of the annuity to be A(t)=$150,000, we want to make deposits every month, or 12 times a year, so n=12, we want to reach our desired value in 30 years, so t=30, and our account earns 7% interest, so r=0.07. We can plug in all of these values and solve for d to find the amount we need to deposit each month:
A(t)150,000150,000150,000d=d[(1+rn)nt−1](rn)=d[(1+0.0712)12⋅30−1]0.0712≈d[(1.00583)360−1]0.00583≈1,219.97d≈122.95
The amount you need to deposit each month is approximately $122.95.
Owen runs 37 miles every 2 weeks. Enter the number of miles Owen runs in 12 weeks
I need someone to write me a narrative on how to solve this problem please!
PLEASE ANSWER ASAP FOR BRAINLEST!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
697.5 ft squared
Step-by-step explanation:
Divide into top two squares and rectangle on bottom so...
(10×7.5)+(8×7.5)×(12.5×45)=area
75+60+562.5=697.5 ft squared
one of the fastest times for 1,500-meter race is 3 minutes and 34 seconds. How many seconds is this time?
Answer:
214 seconds
Step-by-step explanation:
3 times 60 is 180. 180 plus 34 is 214.
(Sorry for my brothers dirty ipad-) but can someone answer this for him? points: 52
Answer:
12 students
Step-by-step explanation:
CLEAN THAT IPAD FOR HIM
Answer:
12 students went to the beach fewer than 2 times.
Step-by-step explanation:
Just count the total number of dots that come before 2.
A research company desires to know the mean consumption of meat per week among males over age 43. A sample of 1384 males over age 43 was drawn and the mean meat consumption was 3 pounds. Assume that the population standard deviation is known to be 1.3 pounds. Construct the 99% confidence interval for the mean consumption of meat among males over age 43. Round your answers to one decimal place.
Answer:
The 99% confidence interval for the mean consumption of meat among males over age 43 is between 2.9 pounds and 3.1 pounds.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.99}{2} = 0.005[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.005 = 0.995[/tex], so Z = 2.575.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
[tex]M = 2.575\frac{1.3}{\sqrt{1384}} = 0.1[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 3 - 0.1 = 2.9 pounds
The upper end of the interval is the sample mean added to M. So it is 3 + 0.01 = 3.1 pounds
The 99% confidence interval for the mean consumption of meat among males over age 43 is between 2.9 pounds and 3.1 pounds.
ANSWER !!
ILL GIVE 40 POINTS !!
DONT SKIP :((
PLUS BRAINLIEST !
Answer:
24 square kilometers
Step-by-step explanation:
Well, this is a trapezoid. The formula for the area of a trapezoid is 1/2 the height times base one plus base two. In other words, 1/2 h x (base 1 + base 2)
So in this case, the two bases are 4 and 12. So we would add the two bases to get 16. Now, we have to half the height. 3 divided by 1/2 is 1.5. So we then do the last step which is multiplying the height by the two bases. So in other words, 1.5 times 16. And 1.5 times 16 is 24. Therefore, the answer is 24 sqaure kilometers.
Answer:
Step-by-step explanation:
,........................................................................................l
David borrows $15,000 for a new car. He is
charged 6% simple interest per year. How much
interest is charged for 5 years?
Is the following relation a function? *
{(-3, 2), (1, 8), (-1, 5), (3, 11)}
Yes
No
Why or why not?
Answer:
No.
Step-by-step explanation:
Well at first glance it might seem so but there are two points particularly that can tell you that these points cannot be within a function.
The points (3,2) and (3,-2) will yield an undefined slope (a straight vertical line). There is no possibility that the other points can be in this line (as their y - values are different) and there is no possibilty that this is a function at all according to the vertical line test (the test is that if you draw a vertical line that there shouldn't be more than one point on it).
Need the answer to x and y !
Answer:
x=5, y=3
Step-by-step explanation:
7x-11=24: 7x=35: x=5
3(5)+9=8x: 24=8x: x=3