Welcome! Check out our free B-School Guides to learn how you compare with other applicants.
Login or Register

Help on some doubts

This topic has 3 member replies
Caps Just gettin' started! Default Avatar
Joined
11 Feb 2007
Posted:
19 messages
Help on some doubts Post Sun Jun 10, 2007 8:47 am
Elapsed Time: 00:00
  • Lap #[LAPCOUNT] ([LAPTIME])
    Hi guys
    Can you help me on some doubts I have on Maths? Please see attach document

    tnks in advanced
    regards
    Caps
    Attachments

    This post contains an attachment. You must be logged in to download/view this file. Please login or register as a user.

    Need free GMAT or MBA advice from an expert? Register for Beat The GMAT now and post your question in these forums!
    vrider Just gettin' started! Default Avatar
    Joined
    01 May 2007
    Posted:
    17 messages
    Post Sun Jun 10, 2007 3:47 pm
    1. 1/x^2+6/x+9 =0

    multiply all terms by x^2
    1+6x+9x^2 = 0

    factorizing, 9x^2 = 3x*3x
    9x^2 + 3x + 3x + 1 = 0

    (3x+1)^2 = 0

    x = -1/3


    2. x^2(x^4+2*x^2-35) = 0

    x^2 = 0 gives x =0 as one root.

    solving for the other polynomial, you'll see
    -35*x^4 = 7*x^2 * -5*x^2

    so, (x^2-5)(x^2+7) =0

    x^2 =5 gives x = +/- rt. 5

    so , 3 real factors.

    I wish I could post it better but typing out exponents & mathematical expressions in text are just painful, so I am trying to shorten it here.

    priyasom Just gettin' started! Default Avatar
    Joined
    29 May 2007
    Posted:
    2 messages
    Post Thu Aug 02, 2007 12:59 am
    3. A sphere with diameter 6 is inscribed into a squared box. What is the greatest stick that we can put between the sphere and the box?


    I have attached a 2D view of a sphere in a square box. We can assume that the edges of the square act as tangents to the circle. Then maximum length of a stick that can be inserted between the sphere and the box will be equal to the radius of the circle = 3.

    Corner right triangle that will be formed will have sides of length 3 each. But we cannot insert a stick of length equal to that of a hypotenuse because it will be blocked by the sphere. Hence maximum length possible is that of the edge of the triangle = radius of the circle = 3.
    Attachments

    This post contains an attachment. You must be logged in to download/view this file. Please login or register as a user.

    givemeanid Really wants to Beat The GMAT!
    Joined
    17 Jun 2007
    Posted:
    277 messages
    Followed by:
    1 members
    Thanked:
    6 times
    Post Thu Aug 02, 2007 8:55 am
    Caps, please post one question per post. This helps to keep everything organized and focused on one topic.

    Also, make sure you post each question in the appropriate section of the forum.

    _________________
    So It Goes

    Best Conversation Starters

    1 melanie.espeland 27 topics
    2 aditya8062 18 topics
    3 Rastis 14 topics
    4 chacha0212 13 topics
    5 yadu9991 12 topics
    See More Top Beat The GMAT Members...

    Most Active Experts

    1 image description GMATGuruNY

    The Princeton Review Teacher

    111 posts
    2 image description Brent@GMATPrepNow

    GMAT Prep Now Teacher

    83 posts
    3 image description CriticalSquareMBA

    Critical Square

    55 posts
    4 image description MBAPrepAdvantage

    MBAPrepAdvantage

    24 posts
    5 image description Jon@Admissionado

    Admissionado

    20 posts
    See More Top Beat The GMAT Experts