find the critical points and classify them as local maxima, local minima, saddle points, or none of these.

Answers

Answer 1
Answer:

This question is incomplete, the complete question is;

find the critical points and classify them as local maxima, local minima, saddle points, or none of these.

f(x,y) = (x + y)(xy + 1)

Answer:

(x,y) = (-1, 1), (1, -1) area critical points

f(xx) =2y, fyy =2x,f(xy) =2x + 2y, D = f(xx)fyy - f(xy²)

at (-1, 1)

f(xx) = 2 ,fyy =-2,f(xy) = 0, D = -4 < 0 saddle point

at (1, -1)

f(xx) = -2, fyy =2,f(xy) =0, D = -4 < 0 saddle point

Step-by-step explanation:

Given that;

f(x,y) = (x + y)(xy + 1)

f(x,y) =x²y + xy² + x + y

for critical points fx =0 ,fy =0

fx = 2xy + y² + 1 = 0, fy = x² + 2xy + 1 = 0

2xy + y² + 1 = 0, x²+ 2xy + 1 = 0

2xy + y² + 1 - x² - 2xy - 1 = 0

x² = y²

=> x = y, x = -y

2xy + y² + 1 = 0, x = y

2yy + y² + 1 = 0

3y² = -1 , no solution

2xy + y² + 1 = 0, x = -y

-2yy + y² + 1 = 0

=> -y2 + 1 = 0

=> y = -1, y = 1  

y = -1 => x = 1, y = 1 => x = -1  

(x,y) = (-1, 1), (1, -1) area critical points

f(xx) =2y, fyy =2x,f(xy) =2x + 2y, D = f(xx)fyy - f(xy²)

at (-1, 1)

f(xx) = 2 ,fyy =-2,f(xy) = 0, D = -4 < 0 saddle point

at (1, -1)

f(xx) = -2, fyy =2,f(xy) =0, D = -4 < 0 saddle point


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27-[38-{46-(15-13-2)}]​
1. Find y, A. and B.

Given: ∠T ≅ ∠V; ST || UVProve: TU || VW

4 connected lines are shown. A line from point S goes slightly down and to the left to point T to form S T. A line from point T goes slightly down and to the right to point U to form T U. A line from point U goes slightly down and to the left to point V to form U T. A line goes slightly down and to the right to point W to form point W.

Complete the two-column proof.
PLEASE HURRYY

Answers

Answer:

Step-by-step explanation:

Given: ∠T ≅ ∠V; ST || UV

Prove: TU || VW

4 connected lines are shown. A line from point S goes slightly down and to the left to point T to form S T. A line from point T goes slightly down and to the right to point U to form T U. A line from point U goes slightly down and to the left to point V to form U T. A line goes slightly down and to the right to point W to form point W.

Complete the two-column proof.

♣ =

✔ alternate interior angles theorem

♦ =

✔ transitive property

♠ =

✔ converse alternate interior angles theorem

just did the assignment

Answer:

Because if ∠T ≅ ∠V, and ST || UV,

the line will go down degrees to form TU || VW.

You have a bowl with 5 orange, 6 blue, 3 green, 4 red and 7 yellow candies. What is the probability that choose an orange candy out of the bowl? ​

Answers

Answer:

20/100 or 20%

Step-by-step explanation:

Let's see how many candies are in total.

5 orange + 6 blue + 3 green + 4 red + 7 yellow = 25 in total

So there are 5/25 orange candies.

5/25 x 4 = 20/100 (I multiplied by 4 to get the denominator 100)

If you need it in percent it is 20%.

I hope this is helpful for you!

You have a litre bottle of water and drink 375 millilitres.
How much is left?

Answers

Answer:

625 ml

Step-by-step explanation:

1 litre is 1000 milliliters

1000 milliliters minus 375 milliliters is 625 milliliters

you have to subtract because you are looking for what is left

your car weighs 7,630 pounds. There is a road safety fee for cars. you fee is $28 plus $0.023 per pound. What is the fee for your car?

Answers

Answer:

Step-by-step explanation:

7630 x .023 = 175.49

175.49 + 28 = $203.49

The sum of two numbers is 87. the difference of two numbers is 65 what are the two numbers

Answers

Step-by-step explanation:

Letthe two numbers be x and y

By the question

x +y =87.....equation (I)

x -y =65......equation (II)

Now adding both equations we get

2x =152

x =152/2

Therefore x =76

Putting x =76in equation i

76+y =87

y =87-76

Therefore y =11

The two numbers are 76and 11.

Hope it helps :)

Answer:

11, 76

Step-by-step explanation:

Let the two numbers be x and y.

According to the given conditions:

x + y = 87.....(1)

x - y = 65....(2)

Adding equations (1) & (2)

x + y = 87

x - y = 65

__________

2x = 152

x = 152/2

x = 76

Plug x = 76 in equation (1)

76 + y = 87

y = 87 - 76

y = 11

Thus the two numbers are 11 and 76.

Please solve this equation​

Answers

Answer:

x = 115° , y = 140° , z = 40°

Step-by-step explanation:

40° , x and 25° lie on a straight line and sum to 180° , that is

x + 40° + 25° = 180°

x + 65° = 180° ( subtract 65° from both sides )

x = 115°

z and 40° are vertically opposite angles and are congruent , then

z = 40°

y and z lie on a straight line and sum to 180° , that is

y + 40° = 180° ( subtract 40° from both sides )

y = 140°