quadratic theory

Question 1

find an unknown value form a quadratic

Answer 1

• b2 - 4ac
• find unknown

Question 2

proving roots are real

Answer 2

• b2-4ac >0
• if value comes out squared instantly real as cannot drop below 0

Question 3

proving no real roots and finding range of value

Answer 3

-b2-4ac <0
- factorise ans
- draw graph

Question 4

showing something is a factor

Answer 4

• synthetic division
• find roots
• see if it divides/ factorises more.