Quadratics Booklet

Question 1

How do you know if a quadratic has a minimum or maximum point

Answer 1

If it has x², there will be a minimum point

If it has -x², there will be a maximum point

Question 2

What is the line of symmetry of a quadratic curve like

Answer 2

It’s always a vertical line through the minimum/maximum point of the curve

Question 3

What is the discriminant and how is it used

Answer 3

b²-4ac
We can use it to tell us how many real roots there are for a quadratic

Question 4

How do you find out how many times a curve and a line intersect using their equations

Answer 4

Substitute one equation into the other, and then use the discriminant like normal.

Question 5

What is the symbol for an empty set in set notation

Answer 5

Ø

Question 6

What is the symbol for a set of all real numbers (including all possible decimals)

Answer 6

ℝ

Question 7

What is the symbol for the set of all integers (including negative numbers and 0)

Answer 7

ℤ

Question 8

What is the symbol for the set of natural numbers and what are natural numbers

Answer 8

ℕ

Natural numbers are all positive integers

Question 9

What is the symbol for ‘is a member of the set’

Answer 9

∈

Question 10

What does ‘x ∈ A’ mean

Answer 10

X is a member of the set A