Answers
(3.1) … … …
[tex]\dfrac{\mathrm dy}{\mathrm dx} = \dfrac{2x-y}{x-2y}[/tex]
Multiply the right side by x/x :
[tex]\dfrac{\mathrm dy}{\mathrm dx} = \dfrac{2-\dfrac yx}{1-\dfrac{2y}x}[/tex]
Substitute y(x) = x v(x), so that dy/dx = x dv/dx + v :
[tex]x\dfrac{\mathrm dv}{\mathrm dx} + v = \dfrac{2-v}{1-2v}[/tex]
This DE is now separable. With some simplification, you get
[tex]x\dfrac{\mathrm dv}{\mathrm dx} = \dfrac{2-2v+2v^2}{1-2v}[/tex]
[tex]\dfrac{1-2v}{2-2v+2v^2}\,\mathrm dv = \dfrac{\mathrm dx}x[/tex]
Now you're ready to integrate both sides (on the left, the denominator makes for a smooth substitution), which gives
[tex]-\dfrac12\ln\left|2v^2-2v+2\right| = \ln|x| + C[/tex]
Solve for v, then for y (or leave the solution in implicit form):
[tex]\ln\left|2v^2-2v+2\right| = -2\ln|x| + C[/tex]
[tex]\ln(2) + \ln\left|v^2-v+1\right| = \ln\left(\dfrac1{x^2}\right) + C[/tex]
[tex]\ln\left|v^2-v+1\right| = \ln\left(\dfrac1{x^2}\right) + C[/tex]
[tex]v^2-v+1 = e^{\ln\left(1/x^2\right)+C}[/tex]
[tex]v^2-v+1 = \dfrac C{x^2}[/tex]
[tex]\boxed{\left(\dfrac yx\right)^2 - \dfrac yx+1 = \dfrac C{x^2}}[/tex]
(3.2) … … …
[tex]y' + \dfrac yx = \dfrac{y^{-3/4}}{x^4}[/tex]
It may help to recognize this as a Bernoulli equation. Multiply both sides by [tex]y^{\frac34}[/tex] :
[tex]y^{3/4}y' + \dfrac{y^{7/4}}x = \dfrac1{x^4}[/tex]
Substitute [tex]z(x)=y(x)^{\frac74}[/tex], so that [tex]z' = \frac74 y^{3/4}y'[/tex]. Then you get a linear equation in z, which I write here in standard form:
[tex]\dfrac47 z' + \dfrac zx = \dfrac1{x^4} \implies z' + \dfrac7{4x}z=\dfrac7{4x^4}[/tex]
Multiply both sides by an integrating factor, [tex]x^{\frac74}[/tex], which gives
[tex]x^{7/4}z'+\dfrac74 x^{3/4}z = \dfrac74 x^{-9/4}[/tex]
and lets us condense the left side into the derivative of a product,
[tex]\left(x^{7/4}z\right)' = \dfrac74 x^{-9/4}[/tex]
Integrate both sides:
[tex]x^{7/4}z=\dfrac74\left(-\dfrac45\right) x^{-5/4}+C[/tex]
[tex]z=-\dfrac75 x^{-3} + Cx^{-7/4}[/tex]
Solve in terms of y :
[tex]y^{4/7}=-\dfrac7{5x^3} + \dfrac C{x^{7/4}}[/tex]
[tex]\boxed{y=\left(\dfrac C{x^{7/4}} - \dfrac7{5x^3}\right)^{7/4}}[/tex]
(3.3) … … …
[tex](\cos(x) - 2xy)\,\mathrm dx + \left(e^y-x^2\right)\,\mathrm dy = 0[/tex]
This DE is exact, since
[tex]\dfrac{\partial(-2xy)}{\partial y} = -2x[/tex]
[tex]\dfrac{\partial\left(e^y-x^2\right)}{\partial x} = -2x[/tex]
are the same. Then the general solution is a function f(x, y) = C, such that
[tex]\dfrac{\partial f}{\partial x}=\cos(x)-2xy[/tex]
[tex]\dfrac{\partial f}{\partial y} = e^y-x^2[/tex]
Integrating both sides of the first equation with respect to x gives
[tex]f(x,y) = \sin(x) - x^2y + g(y)[/tex]
Differentiating this result with respect to y then gives
[tex]-x^2 + \dfrac{\mathrm dg}{\mathrm dy} = e^y - x^2[/tex]
[tex]\implies\dfrac{\mathrm dg}{\mathrm dy} = e^y \implies g(y) = e^y + C[/tex]
Then the general solution is
[tex]\sin(x) - x^2y + e^y = C[/tex]
Given that y (1) = 4, we find
[tex]C = \sin(1) - 4 + e^4[/tex]
so that the particular solution is
[tex]\boxed{\sin(x) - x^2y + e^y = \sin(1) - 4 + e^4}[/tex]
Related Questions
You work at Happy Joe's family restaurant and want to see if customer meal satisfaction and gender are related to one another. You take a sample of customers and ask them if they were satisfied with their meal and note their gender. To determine if Satisfaction and Gender are dependent, what are the appropriate hypotheses
Answers
Answer:
[tex]H_o :[/tex] Satisfaction and Gender are independent of one another
[tex]H_a :[/tex] Satisfaction and Gender are dependent of one another
Step-by-step explanation:
Given
Parameters: Meal satisfaction and Gender
Test: If both parameters are dependent
Required
The appropriate hypotheses
To do this, we set the null hypothesis to independence of both parameters
i.e.
[tex]H_o :[/tex] Satisfaction and Gender are independent of one another
The alternate hypothesis will be the opposite, i.e. dependence of both parameters
i.e.
[tex]H_a :[/tex] Satisfaction and Gender are dependent of one another
when a force of 400N is applied on a body at angle of 60 degree to the horizontal displacement,the body covers a distance of 8m.what is the work done?
Answers
Answer:
1600N
Step-by-step explanation:
Force = 400 N
Angle with horizontal = 60°
Displacement in horizontal direction = 8 m
work done formula when angle is included: Force * distance * cos(angle)
400 * 8 * cos(60)
= 400 * 8 * 1/2
= 1600N
Find the area of the quadrilateral.
Answers
Answer:
320 cm²
Step-by-step explanation:
If 3 units = 12cm
Then 1 unit = 12/3 = 4cm
Formula for Area Trapezoid = height*(base1+base2)/2
Base 1 = 12
Base 2 = 7 * 4 = 28
12 + 28 = 40
40 * (4*4) = 40 * 16 = 640
640 / 2 = 320
If my answer is incorrect, pls correct me!
If you like my answer and explanation, mark me as brainliest!
-Chetan K
The angle of elevation of the top of the tower from a point on the ground is 30 degree, If the height of the tower is 40 space m e t e r s, then the distance between the tower and the point is
Answers
Answer:
[tex]40\sqrt3\ m[/tex]
Step-by-step explanation:
Given that,
The height of the tower, h = 40 m
The angle of elevation is 30°
We need to find the distance between the tower and the point. Let the distance is x. Using trigonometry,
[tex]\tan(30)=\dfrac{h}{x}\\\\\dfrac{1}{\sqrt3}=\dfrac{40}{x}\\\\x=40\sqrt3\ m[/tex]
So, the distance between the tower and the point is equal to [tex]40\sqrt3\ m[/tex].
Why is underfind the square root of a negative number?
Answers
Answer:
The square root of a negative number is undefined, because anything times itself will give a positive (or zero) result. Note: Zero has only one square root (itself). Zero is considered neither positive nor negative
Answer:
sjshzhshshdhdgdgdhdhdgshshshshshwywhwhw
What two methods are the best choices to factor this expression?
18x2 − 8
Answers
Answer:
18x2 is 36 but you have to minus it so the answer is 28.
Examine the following expression.
p squared minus 3 + 3 p minus 8 + p + p cubed
Which statements about the expression are true? Check all that apply.
The constants, –3 and –8, are like terms.
The terms 3 p and p are like terms.
The terms in the expression are p squared, negative 3, 3 p, negative 8, p, p cubed.
The terms p squared, 3 p, p, and p cubed have variables, so they are like terms.
The expression contains six terms.
The terms p squared and p cubed are like terms.
Like terms have the same variables raised to the same powers.
The expression contains seven terms.
Answers
Answer:
the terms in the expression are p squared, negative 3,3p, negative 8,p,p cubed
Step-by-step explanation:
hope that helps
Rewrite in simplest terms: (9x+5)-(-2x+10)(9x+5)−(−2x+10)
Answers
[tex]\implies {\blue {\boxed {\boxed {\purple {\sf { 18 {x}^{2} - 69x - 55}}}}}}[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\orange{Step-by-step\:explanation}}{\orange{:}}}}}[/tex]
[tex] = (9x + 5) - ( - 2 x+ 10)(9x + 5) - ( - 2x + 10)[/tex]
[tex] = (9x + 5) + 2x (9x + 5) - 10(9x + 5) - ( - 2x + 10)[/tex]
[tex] = 9x + 5 + 18 {x}^{2} + 10 x- 90x - 50 + 2x - 10[/tex]
Collect the like terms.
[tex] = 18 {x}^{2} + (9x + 10x- 90x + 2x) + (5 - 50 - 10)[/tex]
[tex] = 18 {x}^{2} + (21x - 90x) +(5 - 60)[/tex]
[tex] = 18 {x}^{2} - 69x - 55[/tex]
[tex]\boxed{ Note:}[/tex][tex]\sf\pink{PEMDAS\: rule.}[/tex]
P = Parentheses
E = Exponents
M = Multiplication
D = Division
A = Addition
S = Subtraction
[tex]\red{\large\qquad \qquad \underline{ \pmb{{ \mathbb{ \maltese \: \: Mystique35♛}}}}}[/tex]
All I need is number one
Answers
Answer:
a. 7 ÷ 4 yes
b. 4 ÷ 7 no
c. [tex]\frac{7}{4}[/tex] yes
d. [tex]\frac{4}{7}[/tex] no
e. 7 × [tex]\frac{1}{4}[/tex] yes
f. [tex]1\frac{3}{4}[/tex] yes
Step-by-step explanation:
hope this helps ^^
p{x:x is a natural number x (9
Answers
Answer:
you need a photo my dude
Step-by-step explanation:
The following figure appears in a math workbook. Students are asked to reflect the polygon across the line, then rotate it 90 degrees clockwise . Which figure shows the result of the two transformations?
Answers
Answer:
C
Step-by-step explanation:
tracing paper is your friend
Using the table above. Which statement below is true?
Answers
9514 1404 393
Answer:
(d) 45% play basketball; 55% play soccer
Step-by-step explanation:
You just need a little number sense here. The total number who play sports is the number in the lower right of the table: 120.
The fraction who are males playing basketball is 42/120. Comparing that to 45/100, we see it cannot be 45%. (a) is false.
The fraction who are males is 72/120, more than half, so cannot be 40%. (b) is false.
Looking at males who play basketball, we have already determined the fraction 42/120 is well below 65%. (c) is false.
The fraction who play basketball is 54/120 = 45%. (d) is true.
in a class of 38 student,30 are good in mathematics and 22 are good in physics how many students are good in both mathematics and physics
Answers
Answer:
8 are bad in math and 16 in physics
Step-by-step explanation:
Find the equivalent exponential expression.
(543
Answers
Answer:
(5) we have multiple the powers
What is the value of x in the figure below? If necessary, round your answer to
the nearest tenth of a unit.
X
15
D 4 B
A. 7.7
B. 3.8
O C. 15
D. 4
Answers
Answer:
Step-by-step explanation:
We know that 1 1 − r = [infinity] n = 0 rn has interval of convergence (−1, 1). This means the series converges for |r| < 1. Therefore, the series f(x) = 1 2 + x = [infinity] n = 0 (−1)n xn 2n + 1 will converge when − x 2 < 1. Thus, what is the interval of convergence for f(x)? (Enter your answer using interval notation.)
Answers
Answer: hello your question is poorly written attached below is the complete question
answer :
I = ( -2, 2 )
Step-by-step explanation:
Determine the internal convergence for f(x)
given that f(x) converges at |-x/2 | < 1
I ( internal convergence for f(x) ) = ( -2, 2 )
Attached below is the detailed solution
find the slope and y-intercept of line 3x +y -9=0
Answers
Answer:
x-intercept(s):(3,0)
y-intercept(s):(0,9)
Step-by-step explanation:
Melanie has D dimes and Q quarters. She has no less than $4 worth of coins altogether. Write this situation as an inequality.
Answers
Step-by-step explanation:
D(.10) + Q(.25) = 4
I think
Answer:
D(.10) + Q(.25) = 4
Step-by-step explanation:
what is the formula for triangle
Answers
Answer:
A = 1/2 b × h
Step-by-step explanation:
hope it helps !!!!
Answer:
The formula for the area of a triangle is 1/2bh.
The sum of four consecutive odd integers is –72. Write an equation to model this situation, and find the values of the four integers.
Answers
9514 1404 393
Answer:
(x -3) +(x -1) +(x +1) +(x +3) = -72-21, -19, -17, -15Step-by-step explanation:
Let x represent the even integer between the middle two odd integers. Then the sum of the four odd integers is ...
(x -3) +(x -1) +(x +1) +(x +3) = -72
4x = -72
x = -18
The four integers are -21, -19, -17, -15.
_____
Additional comment
You could let x represent one of the integers. Often, people choose to let it represent the least of them. Then the equation becomes x +(x+2) +(x+4) +(x+6) = -72, so 4x = -84 and x = -21. This introduces a "subtract 12" step in the solution process that is unnecessary if x is chosen to be the average of the integers.
As the average, x is the sum divided by the number of them, so you know x=-72/4 = -18 immediately. Then you just have to find the nearest two odd integers below and above -18. You can do the whole problem mentally.
Rewrite the expression by factoring out (u-8).3u^2(u-8)-2(u-8)
Answers
Answer:
The rewritten expression is [tex](u - 8)(3u^2 - 2)[/tex]
Step-by-step explanation:
We are given the following expression:
[tex]3u^2(u - 8) - 2(u - 8)[/tex]
Factoring out (u-8)
Place (u-8) to the front, and then divide each term by (u-8). So
[tex]3u^2(u - 8) - 2(u - 8) = (u - 8)\left[\frac{3u^2(u - 8)}{u - 8} - \frac{2(u-8)}{u - 8}\right] = (u - 8)(3u^2 - 2)[/tex]
The rewritten expression is [tex](u - 8)(3u^2 - 2)[/tex]
The time between surface finish problems in a galvanizing process is exponentially distributed with a mean of 41 hours. A single plant operates three galvanizing lines that are assumed to operate independently. Round your answers to four decimal places (e.g. 98.7654).
(a) What is the probability that none of the lines experiences a surface finish problem in 41 hours of operation?
(b) What is the probability that all three lines experience a surface finish problem between 24 and 41 hours of operation?
Answers
Answer:
a) The probability that none of the lines experiences a surface finish problem in 41 hours of operation is 0.0498.
b)The probability that all three lines experience a surface finish problem between 24 and 41 hours of operation is 0.0346.
Step-by-step explanation:
[tex]Mean = \frac{1}{\lambda} = 41\\P(X\leq x)= 1-e^{-\lambda x}[/tex]
[tex]P(X>x)= e^{-\lambda x}[/tex]
a)
[tex]P(x> 41, y>41, Z>41) = (P(X>41))^{3}\\\\P(X>41)=e^{^{-\frac{41}{41}}}=e^{-1}[/tex]
[tex]P(x> 41, y>41, Z>41) = \left (e^{-1} \right )^{3}\\\\P(x> 41, y>41, Z>41) = e^{-3} = 0.0498.[/tex]
b)
[tex]\lambda =\frac{24}{41}\\P(X=1)=e^{-\lambda }\cdot \lambda =\left ( e^{-0.585} \right )\left ( 0.585 \right )\\P(X=1)=0.326[/tex]
For 3 where, P(X=1, Y==1, Z=1)
[tex]= (0.326)^{3} \\\\= 0.0346[/tex]
I’ll mark u plz help
Answers
Answer:
D is the answer
Step-by-step explanation:
all sides and angles are equal
hope it helps!! let me know if it does
The half-life of a newly discovered radioactive element is 30 seconds. To the nearest tenth of a second, how long will it take for a sample of 9 grams to decay to 0.72 grams
Answers
Answer:
It will take about 109.3 seconds for nine grams of the element to decay to 0.72 grams.
Step-by-step explanation:
We can write a half-life function to model our function.
A half-life function has the form:
[tex]\displaystyle A=A_0\left(\frac{1}{2}\right)^{t/d}[/tex]
Where A₀ is the initial amount, t is the time that has passes (in this case seconds), d is the half-life, and A is the amount after t seconds.
Since the half-life of the element is 30 seconds, d = 30. Our initial sample has nine grams, so A₀ is 9. Substitute:
[tex]\displaystyle A=9\left(\frac{1}{2}\right)^{t/30}[/tex]
We want to find the time it will take for the element to decay to 0.72 grams. So, we can let A = 0.72 and solve for t:
[tex]\displaystyle 0.72=9\left(\frac{1}{2}\right)^{t/30}[/tex]
Divide both sides by 9:
[tex]\displaystyle 0.08=\left(\frac{1}{2}\right)^{t/30}[/tex]
We can take the natural log of both sides:
[tex]\displaystyle \ln(0.08)=\ln\left(\left(\frac{1}{2}\right)^{t/30}\right)[/tex]
By logarithm properties:
[tex]\displaystyle \ln(0.08)=\frac{t}{30}\ln(0.5)[/tex]
Solve for t:
[tex]\displaystyle t=\frac{30\ln(0.08)}{\ln(0.5)}\approx109.3\text{ seconds}[/tex]
So, it will take about 109.3 seconds for nine grams of the element to decay to 0.72 grams.
Which would result in a lower price to first discount an item by 10% and then by a further 15%, OR to first discount an item by 15% and then by a further 10%. Justify your reasoning.
Answers
Answer:
Neither one. They will both result in the same price.
Step-by-step explanation:
To discount an item 10%, you charge 90% of the price of the item. To find 90% of a price, you multiply the price by 0.9.
To discount an item 15%, you charge 85% of the price of the item. To find 85% of a price, you multiply the price by 0.85.
Since multiplication is commutative, multiplying a number by 0.9 and then by 0.85 is the same as multiplying the number by 0.85 first and then by 0.9.
Let's say the item costs x.
Take off the 10% discount first: 0.9x
Now take off the 15% discount: 0.85 * (0.9x)
Now do it the other way.
Take off the 15% discount first: 0.85x
Now take off the 10% discount: 0.9 * (0.85x)
Since 0.85 * 0.9 * x = 0.9 * 0.85 * x, the results are the same.
Answer: neither
What is the value of y?
Enter your answer, as an exact value, in the box.
Answers
Answer:
y=4√3 units
Step-by-step explanation:
Hi there!
We are given ΔABC, which is a right triangle (m<C=90°), m<A=60°, AB=8, and BC=y
We need to find the value of y (BC)
The side AB is the hypotenuse of the (the side opposite from the right angle).
BC is a leg, which is a side that makes up the right angle.
Now, if we have a right triangle that has one of the acute angles as 60°, the side OPPOSITE from that 60° angle (in this case, BC) is equal to [tex]\frac{a\sqrt{3}}{2}[/tex], where a is the length of the hypotenuse
Since we have the hypotenuse given as 8, the length of BC (y) is [tex]\frac{8\sqrt{3}}{2}[/tex], or 4√3
so y=4√3 units
Hope this helps!
The formula for the lateral area of a right cone is LA = pi rs, where is the radius of the base and s is the slant height of the cone.
Answers
Answer:
r is the radius of the base and s is the slant height of the cone. From the options given, We can make s the subject of the formula. Hence: Option a) s equals StartFraction L A Over pi r EndFraction
Two equivalent equations are s = LA/πr and r = LA/πs
What is cone?A cone is a shape formed using a series of line segments or lines that connect a common point, called a apex or vertex, to all points on the base of a circle that do not contain a vertex. The distance from the apex of the cone to the base is the height of the cone. A circular base has a measured radius value. And the length from the apex of the cone to any point around the base is the height of the slope. Equations for the surface area and volume of a cone can be derived from these quantities
Volume(V) = ⅓ πr²h cubic units
The total surface area of the cone = πrs + πr²
where, r is radius of the base, s is slant height and h is height of the cone
Given,
Lateral area of cone is denoted by LA
Lateral area of cone = πrs
where r is radius and s is slant height
⇒ LA = πrs
⇒ s = LA/πr
⇒ r = LA/πs
Hence, s = LA/πr and r = LA/πs are two equivalent equations in the given options.
Learn more about cone here:
https://brainly.com/question/16394302
#SPJ7
If A = {x, y, z} then the number of non-empty subsets of A is ________.
a) 8 b) 5 c) 6 d) 7
Answers
Answer:
(d) 7
Step-by-step explanation:
The total number of subsets that can be derived from a set with n elements is given by;
2ⁿ
Out of these subsets, there is one empty set. Therefore, the total number of non-empty subsets is given by;
2ⁿ - 1
Given:
A = {x, y, z}
Set A has 3 elements. This means that n = 3
Therefore, the total number of subsets that can be derived from set A is
2ⁿ = 2³ = 8
One of these 8 subsets is an empty set, therefore, the total number of non-empty subsets of A is;
2ⁿ - 1 = 2³ - 1
8 - 1 = 7
This can be checked by writing all the possible subsets of A as follows;
∅
{x}
{y}
{z}
{x, y}
{y, z}
{x, z}
{x, y, z}
Removing the empty set ∅, the non-empty subsets of A are;
{x}
{y}
{z}
{x, y}
{y, z}
{x, z}
{x, y, z}
I need help please it’s for math
Answers
Answer:
139
Step-by-step explanation:
Since the given is a parallelogram then angle <D and angle <B are equal angles
10x - 21 = 9x - 5
10x - 9x = 21 - 5
x = 16 replace x with 16 to find the measure of angle <B
16*9 - 5 = 139
for a science fair project javier is recording the amount of water that evaporate from a bucket in a month he creates a table like this i will give point for the best answer
week 1 2/16 inch
week 2 1/16 inch
week 3 3/16 inch
week 4 2/16 inch
how much water had evaported from the bucket at the end of week 2
what was the total amount of water that evaported in the four weeks
if javier orignally put 4 inches of water in the bucket how many inches of water were left after the experment was completed
Answers
Answer: [tex]\dfrac{3}{16},\ \dfrac{1}{2}, \dfrac{7}{2}\ \text{inch}[/tex]
Step-by-step explanation:
Given
Javier created a table for the amount of water evaporated in each week
After two weeks, the amount of water evaporated is
[tex]\Rightarrow \dfrac{2}{16}+\dfrac{1}{16}\\\\\Rightarrow \dfrac{2+1}{16}=\dfrac{3}{16}\ \text{inch}[/tex]
Total amount of water evaporated in four weeks is
[tex]\Rightarrow \dfrac{2}{16}+\dfrac{1}{16}+\dfrac{3}{16}+\dfrac{2}{16}\\\\\Rightarrow \dfrac{2+1+3+2}{16}=\dfrac{8}{16}\\\Rightarrow \dfrac{1}{2}\ \text{inch}[/tex]
If Javier originally puts 4 inches of water, amount of water left in the bucket
[tex]\Rightarrow 4-\dfrac{1}{2}\\\\\Rightarrow \dfrac{4\times 2}{2}-\dfrac{1}{2}\\\\\Rightarrow \dfrac{8-1}{2}=\dfrac{7}{2}\ \text{inch}[/tex]
