Mathmatical Studies - Unit 2 > Imaginary
 
 

Revision

Remember from Unit 1 the solutions of a quadratic equation ax2+bx+c=0 can be found from the formula:

  1. b2-4ac > 0   real distinct roots
  2. b2-4ac = 0   real repeated roots
  3. b2-4ac < 0   non real roots

These can be represented graphically as follows:

1.

1. Crosses x axis in two places.    

2.

  ii. Touches x axis once.  

3.

    iii. Does not make contact with x axis.