If A=P+I make the subject as P

Let φ(x, y) = arctan (y/x) .

Alexandra [31]

Answer:

a) $\large F(x,y)=(-\frac{y}{x^2+y^2},\frac{x}{x^2+y^2})$

b) $\large \mathbb{R}^2-\{(0,0)\}$

c) the points of the form (x, -x) for x≠0

Step-by-step explanation:

a)

If φ(x, y) = arctan (y/x), the vector field F = ∇φ would be

$\large F(x,y)=(\frac{\partial \phi}{\partial x},\frac{\partial \phi}{\partial y})$

On one hand we have,

$\large \frac{\partial \phi}{\partial x}=\frac{\partial arctan(y/x)}{\partial x}=\frac{-y/x^2}{1+(y/x)^2}=-\frac{y/x^2}{1+y^2/x^2}=\\\\=-\frac{y/x^2}{(x^2+y^2)/x^2}=-\frac{y}{x^2+y^2}$

On the other hand,

$\large \frac{\partial \phi}{\partial y}=\frac{\partial arctan(y/x)}{\partial y}=\frac{1/x}{1+(y/x)^2}=\frac{1/x}{1+y^2/x^2}=\\\\=\frac{1/x}{(x^2+y^2)/x^2}=\frac{x}{x^2+y^2}$

So

$\large F(x,y)=(-\frac{y}{x^2+y^2},\frac{x}{x^2+y^2})$

b)

The domain of definition of F is

$\large \mathbb{R}^2-\{(0,0)\}$

i.e., all the plane X-Y except the (0,0)

c)

Here we want to find all the points such that

$\large (-\frac{y}{x^2+y^2},\frac{x}{x^2+y^2})=(k,k)$

where k is a real number other than 0.

But this means

$\large -\frac{y}{x^2+y^2}=\frac{x}{x^2+y^2}\Rightarrow y=-x$

So, all the points in the line y = -x except (0,0) are parallel to the vector field F, that is, the points (x, -x) with x≠ 0

8 0

3 years ago

Use the boundedness theorem to determine whether the polynomial function satisfies the given condition. The polynomial f(x) = x4

7nadin3 [17]

Answer:

So f(x) has no real greater than 8. Step - by - step explanation is shown in the attachment.

Step-by-step explanation:

Let f ( x) be a polynomial with real coefficients and with a positive lending coefficient.

If f(x) is divided by x-c and

a) if c>0 and all number in the bottom row of the synthetic division are non negative , then f(x) has no zero greater than c.

b ) if c<0 and the number in the bottom row of the synthetic division alternate in sign then f (x) has no zero less than c

As shown in the figure

Since the number in the bottom row of the synthetic division alternate in sign

So f(x) has no real greater than 8

6 0

3 years ago

I PROMISE BRAINLIST... IT'S SIMPLE PLEASEEEE

ser-zykov [4K]

Answer:

11. 3^2 • 3^5 < 3^8

12. 3^3 • 3^3 > 3^5

13. Option C.

Step-by-step explanation:

11. Which of the following expressions is true?

A. 4^3• 4^4 = 412

4^3• 4^4 = 4^7 = 16384 ❌

B. 5^2 • 5^3 > 5^5

5^2 • 5^3 = 5^5 ❌

C. 3^2 • 3^5 < 3^8

3^2 • 35 = 315 ✔️

D. 5^2 • 54 = 58

5^2 • 54 = 1350 ❌

12. Which of the following expressions is true?

A. 8^3 • 8^2 < 8^4

8^3 • 8^2 = 8^5 ❌

B. 4^4 • 4^4 = 4^16

4^4 • 4^4 = 4^8 ❌

C. 2^2 • 2^6 < 2^8

2^2 • 2^6 = 2^8 ❌

D. 3^3 • 3^3 > 3^5

3^3 • 3^3 = 3^6 ✔️

13. Write the value of the expression: 3^4/3^4

3^4/3^4 = 1

The correct answer is C. 1 ✔️

4 0

3 years ago

Solve for x: 4 over 5 x + 4 over 3 = 2x x =

Naily [24]

Answer:

over 5 x + 4 over 3 = 2x

can't find x

Hi McDa:

Here's a couple hints. (I have no idea what you already understand. Please check out our posting guidelines.)

Express the Natural number 3 in Rational form 3/1.

4

5

x

+

4

3

1

=

2

x

Regarding the left-hand side above, have you learned the property that says we may multiply by the reciprocal of 3/1, instead of dividing by 3/1?

Step-by-step explanation: Incorrect? Let me know!

8 0

3 years ago

5(n–2)=5n–10 What is the awnser

Leokris [45]

Answer:

Anything

Step-by-step explanation:

5n - 10 = 5n - 10

It doesn't matter what you put in for n, the equality can never be anything but an equality.

Suppose n = 10,000,000

Then 5*10,000,000 - 10 = 5*10,000,000

6 0

3 years ago

Read 2 more answers