Question

y’’ -4y’ +4y = (12x^2 -6x)e^2x Y(0)= 1 Y’(0)=0 Y(x)=c1y1+c2y2+yp

76

likes
379 views

Answer to a math question y’’ -4y’ +4y = (12x^2 -6x)e^2x Y(0)= 1 Y’(0)=0 Y(x)=c1y1+c2y2+yp

Expert avatar
Corbin
4.6
104 Answers
To solve the given second-order linear homogeneous ordinary differential equation:
y'' - 4y' + 4y = (12x^2 - 6x)e^{2x}
We first find the complementary function (CF) by solving the associated homogeneous equation:
y'' - 4y' + 4y = 0
The auxiliary equation is obtained by substituting y = e^{rx} into the homogeneous equation:
r^2e^{rx} - 4re^{rx} + 4e^{rx} = 0
Factoring out e^{rx}:
e^{rx}(r^2 - 4r + 4) = 0
Simplifying the quadratic equation:
r^2 - 4r + 4 = (r-2)^2 = 0
This implies a repeated root at r = 2, so the complementary function (CF) is:
y_{CF} = (c_1 + c_2x)e^{2x}

To find the particular integral (PI), we use the method of undetermined coefficients. Let's assume the particular solution is of the form:
y_{PI} = Ax^2e^{2x} + Bxe^{2x}
Now, let's find the first and second derivatives of y_{PI}:
y'_{PI} = (2Ax^2e^{2x} + 2Axe^{2x}) + (Be^{2x} + 2Bxe^{2x})
y''_{PI} = (4Ax^2e^{2x} + 8Axe^{2x} + 2Ae^{2x}) + (2Be^{2x} + 4Be^{2x} + 2Bxe^{2x})
Substituting these derivatives into the original differential equation and simplifying, we get:
(4Ax^2 + 12Bx + 12A - 6B)e^{2x} = (12x^2 - 6x)e^{2x}

Comparing coefficients, we have:
4Ax^2 + 12Bx + 12A - 6B = 12x^2 - 6x
Equating the coefficients of like powers of x:
4A = 12 \quad \text{(coefficient of }x^2)
12B + 12A - 6B = -6 \quad \text{(coefficient of }x)

Solving the equations, we find:
A = 3
B = -1

Therefore, the particular solution (PI) is:
y_{PI} = 3x^2e^{2x} - xe^{2x}

The general solution (GS) is the sum of the complementary function (CF) and the particular integral (PI):
y_{GS} = y_{CF} + y_{PI} = (c_1 + c_2x)e^{2x} + 3x^2e^{2x} - xe^{2x}

Using the initial conditions, we can find the values of c_1 and c_2. Given: y(0) = 1 and y'(0) = 0.

Substituting x = 0 and y = 1 into the general solution (GS):
y_{GS}(0) = (c_1 + c_2 \cdot 0)e^{2 \cdot 0} + 3 \cdot 0^2 e^{2 \cdot 0} - 0 \cdot e^{2 \cdot 0} = c_1 = 1

Substituting x = 0 and y' = 0 into the general solution (GS):
y'_{GS}(0) = (c_2)e^{2 \cdot 0} + 0 - 1 \cdot e^{2 \cdot 0} = c_2 - 1 = 0

Solving for c_2, we get:
c_2 = 1

Therefore, the solution to the differential equation is:
y(x) = (1 + x)e^{2x} + 3x^2e^{2x} - xe^{2x}

Answer: y(x) = (1 + x + 3x^2 - x)e^{2x} = (1 + 2x + 3x^2)e^{2x}

Frequently asked questions (FAQs)
What is the y-intercept of the logarithmic function y = log(x)?
+
What is the equation of an ellipse with center at (3, -2), major axis length 10, and minor axis length 6?
+
Question: What is the graph of the logarithmic function f(x) = log(base 2)(x+3) when x is between -5 and 5, inclusive?
+
New questions in Mathematics
A particular employee arrives at work sometime between 8:00 a.m. and 8:50 a.m. Based on past experience the company has determined that the employee is equally likely to arrive at any time between 8:00 a.m. and 8:50 a.m. Find the probability that the employee will arrive between 8:05 a.m. and 8:40 a.m. Round your answer to four decimal places, if necessary.
-x+3x-2,si x=3
To calculate the probability that a player will receive the special card at least 2 times in 8 games, you can use the binomial distribution. The probability of receiving the special card in a single game is 1/4 (or 25%), and the probability of not receiving it is 3/4 (or 75%).
11(4x-9)= -319
A car tire can rotate at a frequency of 3000 revolutions per minute. Given that a typical tire radius is 0.5 m, what is the centripetal acceleration of the tire?
Let X be a discrete random variable with range {1, 3, 5} and whose probability function is f(x) = P(X = x). If it is known that P(X = 1) = 0.1 and P(X = 3) = 0.3. What is the value of P(X = 5)?
What is the amount of interest of 75,000 at 3.45% per year, at the end of 12 years and 6 months?
A car that starts from rest moves for 11 min, reaching a speed of 135 km/h, calculate the acceleration it had
The mean temperature for july in H-town 73 degrees fahrenheit. Assuming that the distribution of temperature is normal what would the standart deviation have to be if 5% of the days in july have a temperature of at least 87 degrees?
Divide 22 by 5 solve it by array and an area model
Suppose you have a sample of 100 values from a population with mean mu = 500 and standard deviation sigma = 80. Given that P(z < −1.25) = 0.10565 and P(z < 1.25) = 0.89435, the probability that the sample mean is in the interval (490, 510) is: A)78.87% B)89.44% C)10.57% D)68.27%
Determine the increase of the function y=4x−5 when the argument changes from x1=2 to x2=3
The probability of growing a seedling from a seed is 0.62. How many seeds do I need to plant so that the probability of growing at least one seedling is greater than or equal to 0.87?
Sections of steel tube having an inside diameter of 9 inches, are filled with concrete to support the main floor girder in a building. If these posts are 12 feet long and there are 18 of them, how many cubic yards of concrete are required for the job?
Let x be an integer. Prove that x^2 is even if and only if is divisible by 4.
solid obtained by rotation around the axis x = -1, the region delimited by x^2 - x + y = 0 and the abscissa axis
You buy a $475,000 house and put 15% down. If you take a 20 year amortization and the rate is 2.34%, what would the monthly payment be?
2+2020202
Write decimal as the fraction 81/125 simplified
(3.1x10^3g^2)/(4.56x10^2g)