Here we will look at some more complicated circle questions. The videos from the previous circles blog will help.

June 14 Question 7 – answer here

January 12 Question 7 – answer here

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# Tag: discriminant

## Core 1 – Circles continued

## Core 1 – discriminant

Here we will look at some more complicated circle questions. The videos from the previous circles blog will help.

June 14 Question 7 – answer here

January 12 Question 7 – answer here

Yesterday we looked at solving inequalities. This topic is often combined with use of the discriminant. The discriminant (D = b^{2} – 4ac) tells you how many roots a quadratic of the form ax^{2} + 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