Turn on thread page Beta
    • Thread Starter

    HI guys.

    I have an equation of a curve y=x4-2x3-10x2+5x+30 It crosses the x axis at A and B. B has an x value that isn't an integer, A is an integer.

    I've used the factor theorem to show x-2 is a factor.

    I have wrote the value of a and found a cubic equation satisfied by B by using long division.

    I've showed that if the iterative formula Xn+1 = cubedroute(10Xn+15) coverges, then it converges to B. Which I worked out to be 3.743.

    Now I need to use the iterative formula with a suitable starting value to find the value of B. How do I do this because I thought that 3.743 was the answer to this?

    Appreciate any help. Thanks
    • Thread Starter

    Another question is:

    The sequence defined by the iterative formula Xn+1=cubedroute(17-5Xn) with x1=2 converges to A. Using the formula to find a to 2dp. You should show the result of each iteration. How do i do this?

Submit reply
Turn on thread page Beta
Updated: September 27, 2011

University open days

  • Heriot-Watt University
    School of Textiles and Design Undergraduate
    Fri, 16 Nov '18
  • University of Roehampton
    All departments Undergraduate
    Sat, 17 Nov '18
  • Edge Hill University
    Faculty of Health and Social Care Undergraduate
    Sat, 17 Nov '18
Have you ever experienced bullying?
Useful resources

Make your revision easier


Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here


How to use LaTex

Writing equations the easy way


Best calculators for A level Maths

Tips on which model to get

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.