Quadratic Function

Question 0

Quadratic inequalities

Answer 0

Sketch graph

• factorise ( make f(x) = 0 )
• answer question. >/< 0

Question 1

Axis of symmetry

Answer 1

X = -b/2a

Question 2

Roots of a quadratic

Answer 2

a>0 with 2 roots = indefinite function

a<0 with 2 roots = indefinite function

Question 3

The discriminant

Question 4

Quadratic identities

Answer 4

Two quadratic functions and they are equal for three values of x then they are identically equal.

Expand and subtract two equations, if equal to zero it is an identity.

Question 5

Sum and product of roots

Answer 5

Alpha + beta = -b/a

Alpha beta = c/a

Alpha^2 + beta^2 = alpha^2 + beta^2 - 2AB

1/A + 1/B = common denominator

Question 6

Equations reducible to quadratics

Answer 6

(x+2)^2 - 3(x+2) - 4 = 0
Let u = x+2
Factorise
Sub u in