GATE Exam  >  GATE Questions  >  Consider the initial value problem below. The... Start Learning for Free
Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .
dy/dx = 2x - y, y(0) = 1
    Correct answer is '0.886'. Can you explain this answer?
    Verified Answer
    Consider the initial value problem below. The value of y at x = ln 2. ...
    dy/dx = 2x - y, y(0) = 1, y at x = ln 2
    dy/dx + y = 2x
    P =1, Q =2x

    Solution, y(I.F)= ∫Q (I.F .)dx
    yex = ∫ 2x ⋅exdx = 2(xex −ex)+ C
    y =2x – 2 + ce–x
    y(0) = 1
    1 = 0 – 2 + C
    C = 3
    ∴ y =2x – 2 + 3e–x
    At x = ln 2
    y = 2(ln 2) – 2 + 3e–ln2​
    1.386 - 2 + 3/2 = 0.886
    View all questions of this test
    Most Upvoted Answer
    Consider the initial value problem below. The value of y at x = ln 2. ...
    To solve the given initial value problem, we can use the method of integrating factors.

    Step 1: Write the given differential equation in standard form
    The given differential equation is dy/dx = 2x - y.

    Step 2: Identify the coefficients
    The coefficients of x and y in the given differential equation are 2 and -1, respectively.

    Step 3: Find the integrating factor
    The integrating factor (IF) is given by e^(∫P(x)dx), where P(x) is the coefficient of x. In this case, P(x) = 2. Therefore, the integrating factor is IF = e^(∫2dx) = e^(2x).

    Step 4: Multiply the differential equation by the integrating factor
    Multiplying both sides of the differential equation dy/dx = 2x - y by the integrating factor e^(2x), we get e^(2x)dy/dx - e^(2x)y = 2xe^(2x) - ye^(2x).

    Step 5: Apply the product rule of differentiation
    The left side of the equation can be written as d(ye^(2x))/dx using the product rule of differentiation.

    Step 6: Integrate both sides of the equation
    Integrating both sides of the equation, we get ∫d(ye^(2x))/dx dx = ∫(2xe^(2x) - ye^(2x)) dx.

    Simplifying the integral on the left side, we get ye^(2x) = ∫(2xe^(2x) - ye^(2x)) dx.

    Integrating the terms on the right side, we get ye^(2x) = x^2e^(2x) + C, where C is the constant of integration.

    Step 7: Solve for y
    Solving for y, we divide both sides of the equation by e^(2x), y = x^2 + Ce^(-2x).

    Step 8: Apply the initial condition
    Using the initial condition y(0) = 1, we can substitute x = 0 and y = 1 into the equation y = x^2 + Ce^(-2x) to find the value of C.

    1 = 0^2 + Ce^(-2*0)
    1 = 0 + C

    Therefore, C = 1.

    Step 9: Substitute the value of C
    Substituting the value of C into the equation y = x^2 + Ce^(-2x), we get y = x^2 + e^(-2x).

    Step 10: Find the value of y at x = ln 2
    To find the value of y at x = ln 2, we substitute x = ln 2 into the equation y = x^2 + e^(-2x).

    y = (ln 2)^2 + e^(-2*ln 2)
    y = ln^2 2 + e^(-ln 4)
    y = ln^2 2 + 1/4
    y = ln^2 2 + 0.25
    y ≈ 0.693 + 0.
    Explore Courses for GATE exam

    Similar GATE Doubts

    Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer?
    Question Description
    Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer?.
    Solutions for Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? in English & in Hindi are available as part of our courses for GATE. Download more important topics, notes, lectures and mock test series for GATE Exam by signing up for free.
    Here you can find the meaning of Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer?, a detailed solution for Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? has been provided alongside types of Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Consider the initial value problem below. The value of y at x = ln 2. (rounded off to 3 decimal places) is ________ .dy/dx = 2x - y, y(0) = 1Correct answer is '0.886'. Can you explain this answer? tests, examples and also practice GATE tests.
    Explore Courses for GATE exam
    Signup for Free!
    Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
    10M+ students study on EduRev