Results 1 to 3 of 3

Math Help - Finding the co-ords where y = 0..

  1. #1
    Member
    Joined
    Nov 2007
    Posts
    100

    Finding the co-ords where y = 0..

    y = x^{1/3} - x^2

    How do I solve this equation to find the roots. It's not a quadratic equation because it involves cubic root of x.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Nov 2008
    Posts
    461
    Hi there!

    Quote Originally Posted by struck View Post
    y = x^{1/3} - x^2

    How do I solve this equation to find the roots. It's not a quadratic equation because it involves cubic root of x.
    I would try:

    0 = x^{1/3} - x^2

    x^2 = x^{1/3}

    next step: (both sides)^3

    (x^2)^3 = x^1

    x^6 = x^1

    0 = x^6 - x^1

    0 = x (x^5 - 1)

    => x = 0 or x=1 (solving x^5 = 1 leads to x = 1)
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    11,621
    Thanks
    426
    Quote Originally Posted by struck View Post
    y = x^{1/3} - x^2

    How do I solve this equation to find the roots.
    0 = x^{\frac{1}{3}} - x^2

    0 = x^{\frac{1}{3}}\left(1 - x^{\frac{5}{3}}\right)


    x^{\frac{1}{3}} = 0 ... x = 0

    x^{\frac{5}{3}} = 1 ... x = 1
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 4
    Last Post: December 23rd 2011, 05:00 AM
  2. Replies: 7
    Last Post: April 10th 2011, 03:51 AM
  3. Double integrals with polar co-ords
    Posted in the Calculus Forum
    Replies: 6
    Last Post: April 10th 2011, 01:53 AM
  4. Vector Calculus in Spherical Polar Co-ords.
    Posted in the Calculus Forum
    Replies: 1
    Last Post: November 26th 2008, 09:18 AM
  5. Co-ords intersection
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: December 11th 2007, 11:48 AM

Search Tags


/mathhelpforum @mathhelpforum