1634/19 long division

In this problem we consider an equation in differential form Mdx+Ndy=0. (4x+2y)dx+(2x+8y)dy=0 Find My= 2 Nx= 2 If the problem is

zheka24 [161]

Answer:

$f(x,y)=2x^2+4y^2+2xy=C_1\\\\Where\\\\y(x)=\frac{1}{4} (-x\pm \sqrt{-7x^2+C_1} )$

Step-by-step explanation:

Let:

$M(x,y)=4x+2y\\\\and\\\\N(x,y)=2x+8y$

This is and exact equation, because:

$\frac{\partial M(x,y)}{\partial y} =2=\frac{\partial N}{\partial x}$

So, define f(x,y) such that:

$\frac{\partial f(x,y)}{\partial x} =M(x,y)\\\\and\\\\\frac{\partial f(x,y)}{\partial y} =N(x,y)$

The solution will be given by:

$f(x,y)=C_1$

Where C1 is an arbitrary constant

Integrate $\frac{\partial f(x,y)}{\partial x}$ with respect to x in order to find f(x,y):

$f(x,y)=\int\ {4x+2y} \, dx =2x^2+2xy+g(y)$

Where g(y) is an arbitrary function of y.

Differentiate f(x,y) with respect to y in order to find g(y):

$\frac{\partial f(x,y)}{\partial y} =2x+\frac{d g(y)}{dy}$

Substitute into $\frac{\partial f(x,y)}{\partial y} =N(x,y)$

$2x+\frac{dg(y)}{dy} =2x+8y\\\\Solve\hspace{3}for\hspace{3}\frac{dg(y)}{dy}\\\\\frac{dg(y)}{dy}=8y$

Integrate $\frac{dg(y)}{dy}$ with respect to y:

$g(y)=\int\ {8y} \, dy =4y^2$

Substitute g(y) into f(x,y):

$f(x,y)=2x^2+4y^2+2xy$

The solution is f(x,y)=C1

$f(x,y)=2x^2+4y^2+2xy=C_1$

Solving y using quadratic formula:

$y(x)=\frac{1}{4} (-x\pm \sqrt{-7x^2+C_1} )$

4 0

3 years ago

The subtraction property of equality states that the two sides of an

yawa3891 [41]

Answer:

False

Step-by-step explanation:

The answer is in its name. Its a property of equality meaning it makes sure that both sides are equal to each other

3 0

1 year ago

I need your help!!

Irina18 [472]

Carla ants you to create a course about a personality inventory. She says the course will help managers be more empathetic. She’s already created a slide deck,so it should be easy!

There is your scenario hope this helped oh and can you mark me brainliest

4 0

2 years ago

Identify terms and factors: - 4x + 2x2<br>y

DedPeter [7]

Answer:

=2x2y−4x

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

The population of a particular type of bacteria is known to triple in 22 days. What is the daily growth rate

Paul [167]

Answer: ∛(3)

Step-by-step explanation:

Suppose that at day 0 the population was A.

at day 3, the population will be: 3*A

at day 6, the population will be 3*(3*A) = A*3^2

then, at day N = 3*n (where n = 0, 1, 2.....) the population will be:

P(N) = A*3^n

Particularly, if we take n = 1/3 we will have:

N = 3*1/3 = 1

This means that this is the first day after the day 0.

P(1) = A*3^(1/3)

(then in day one, the population grow by a factor of 3^(1/3))

N = 2 is when n = 2/3, then:

P(2) = A*3^(2/3)

The quotient between P(2) and P(1) is equal to the growth between day one and day two, this should be the same as the growth between day zero and day one.

A*3^(2/3)/(A*3^(1/3)) = 3^( 2/3 - 1/3) = 3^(1/3)

So we found that the daily growth rate is 3^(1/3) or ∛(3)

3 0

3 years ago