Quadratic Functions
Find the x-intercepts:
y=x2-9
x=3
x=-3
Expand and Simplify
(x+4) (x+1)
x2+5x+4
f(x)=x2-4x+3
Find: f(2)
f(2)=1
Find the vertex of the quadratic:
y=x2+4x+1
Vertex:(-2,-3)
Factor completely:
x2+6x+8
(x+2)(x+4)
Solve using factoring:
y=2x2-5x-3
x=3
x=-1/2
Factor:
2x2+7x+3
(2x+1)(x+3)
Solve using the quadratic formula
y=x2-4x+1
x=2+- √3
x2-10x+9
(x-5)2-16
A ball is thrown upward. Its height (in metres) is given by:
h(t)=-5t2+20t+1
a) when does the ball reach its maximum height ?
b) What is the maximum height ?
Time of max height: t=2 seconds
Maximum height: 21 metres
Solve:
x2+5x+6=0
x=-2 or x=-3