Core 1 – discriminant

Yesterday we looked at solving inequalities. This topic is often combined with use of the discriminant. The discriminant (D = b2 – 4ac) tells you how many roots a quadratic of the form ax2 + bx + c = 0 has.

if

D > 0, there are two distinct and real roots

D = 0, there is one repeated root

D < 0, there are no real roots

 

Watch the video below and then try the exam questions

January 2006 question 4 – answers here

June 2013 question 7 – answer here

Most question though are harder than this, take a look through some of these videos and then try the exam question below.

January 2013 Question 8 – answer here

Core 1 – Quadratics 2

Today we will continue looking at quadratics, this time sketching them.

Finish the exam questions from yesterday and see how it goes. If you get stuck then look at the video. If you are still stuck and are a New College student then head over to our Facebook Support Group and someone there will be able to help!

Jan 2008 q 5 (the whole question thime) – answer here

June 2008 q 4 (the whole question this time)- answer here

You could also try a whole question from scratch – Jan 2013 q 4 – answer here

Core 1 – Quadratics 1

Today we will start looking at quadratics, namely completing the square.

Try the exam questions and see how it goes. If you get stuck then look at the video. If you are still stuck and are a New College student then head over to our Facebook Support Group and someone there will be able to help!

June 2008 q 4 (do a minimum of part a)- answer here

Jan 2008 q 5 (do a minimum of part a and b) – answer here

Below is a video on completing the square. On this page are also some other videos which will help with completing the square.