Turn on thread page Beta
    • Thread Starter

    Express X2-4root2x+5 as a(x+b)2+c
    Can someone work this out please
    Posted on the TSR App. Download from Apple or Google Play

    (Original post by Me100)
    Express X2-4root2x+5 as a(x+b)2+c
    Can someone work this out please
    I assume the original expression is  x^2-4\sqrt{2}x+5? Do you know about completing the square? If so, what have you tried so far?

    we are not allowed to give full solutions.

    in general if you have

    y = x2 + bx + c

    you start off by dividing b by 2:

    y = ( x + b/2 )2 + *

    now square (b/2)... and find how to get from that number to c by adding or subtracting a suitable amount *
Submit reply
Turn on thread page Beta
Updated: October 27, 2017

University open days

  • University of Exeter
    Undergraduate Open Days - Exeter Campus Undergraduate
    Wed, 24 Oct '18
  • University of Bradford
    Faculty of Health Studies Postgraduate
    Wed, 24 Oct '18
  • Northumbria University
    All faculties Undergraduate
    Wed, 24 Oct '18
Who do you think it's more helpful to talk about mental health with?
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.