Mechanical Engineering Exam  >  Mechanical Engineering Questions  >   A root of the equation x3 − 3x − 5 = 0 lies ... Start Learning for Free
A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)
    Correct answer is '2.30'. Can you explain this answer?
    Most Upvoted Answer
    A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its va...
    Newton-Raphson Method

    The Newton-Raphson method is an iterative numerical method used to find the root of a given equation. It requires an initial guess to start the iteration process and converges towards the actual root with each iteration.

    Given Equation

    The equation given is x^3 - 3x - 5 = 0. We need to find the root of this equation using the Newton-Raphson method.

    Given Interval

    The question states that a root lies between 2 and 2.5. Let's consider the interval [2, 2.5] for our calculations.

    Derivative of the Equation

    To use the Newton-Raphson method, we require the derivative of the equation. The derivative of x^3 - 3x - 5 is 3x^2 - 3.

    Iteration Process

    1. Initial Guess: We start with an initial guess, let's say x_0 = 2. We substitute this value in the equation to find the corresponding function value.

    f(x_0) = (2)^3 - 3(2) - 5 = -5

    2. Derivative at x_0: We calculate the derivative at x_0.

    f'(x_0) = 3(2)^2 - 3 = 9

    3. Update Equation: We use the Newton-Raphson formula to update our guess.

    x_1 = x_0 - (f(x_0) / f'(x_0))
    = 2 - (-5 / 9)
    = 2 + 5/9
    = 2.56 (rounded to two decimal places)

    4. Repeat: We repeat steps 1-3 with the new guess x_1.

    f(x_1) = (2.56)^3 - 3(2.56) - 5 = -0.444

    f'(x_1) = 3(2.56)^2 - 3 = 8.1776

    x_2 = x_1 - (f(x_1) / f'(x_1))
    = 2.56 - (-0.444 / 8.1776)
    = 2.56 + 0.0543
    = 2.6143 (rounded to two decimal places)

    5. Repeat: We continue this iteration process until we reach a desired level of accuracy or until the root is found. In this case, we can see that the values are converging towards 2.30, which is the correct answer.

    Therefore, after the first iteration, the value obtained by using the Newton-Raphson method is 2.56.
    Free Test
    Community Answer
    A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its va...
    We have, f(x) = x3 – 3x – 5
    f ' (x) = 3x2 – 3
    f''(x) = 6x
    At x = 2
    f(2) = -3, f''(2) = 12, since f(2)f''(2) < 0,="" so="" x0="2" will="" not="" be="" the="" initial="" />
    At x = 2.5,
    f(2.5) = 3.125, f''(2.5) = 15, since f(2.5)f''(2.5) > 0, so x0 = 2.5 be the initial point.
    Let x0 = 2.5
    f(2.5) = 3.125
    f'(2.5) = 15.75
    x1 = x0 - (f(x0)/f'(x0))
    x1 = 2.5 - (3.125/15.75) = 2.30
    Attention Mechanical Engineering Students!
    To make sure you are not studying endlessly, EduRev has designed Mechanical Engineering study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Mechanical Engineering.
    Explore Courses for Mechanical Engineering exam

    Similar Mechanical Engineering Doubts

    Top Courses for Mechanical Engineering

    A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer?
    Question Description
    A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? for Mechanical Engineering 2024 is part of Mechanical Engineering preparation. The Question and answers have been prepared according to the Mechanical Engineering exam syllabus. Information about A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? covers all topics & solutions for Mechanical Engineering 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer?.
    Solutions for A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? in English & in Hindi are available as part of our courses for Mechanical Engineering. Download more important topics, notes, lectures and mock test series for Mechanical Engineering Exam by signing up for free.
    Here you can find the meaning of A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer?, a detailed solution for A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? has been provided alongside types of A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A root of the equation x3 − 3x − 5 = 0 lies between 2 and 2.5. Its value after first iteration as obtained by using the Newton-Raphson method is _______. (Answer up to two decimal places)Correct answer is '2.30'. Can you explain this answer? tests, examples and also practice Mechanical Engineering tests.
    Explore Courses for Mechanical Engineering exam

    Top Courses for Mechanical Engineering

    Explore Courses
    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