Quadratic Functions
Find the vertex:
f(x) = -2(x + 3)2 + 5
(-3, 5)
What is i equivalent to?
The square root of -1
Solve:
x2 + 6x + 5 = 0
x = -1 and x = -5
What are the solutions?
x = -2 and x = 3
What is the graph of a quadratic function called?
parabola
Find the y-intercept coordinate point:
f(x) = (x - 5)(x - 3)
(0, 15)
Simplify the expression:
7i - (2 - 3i) + 5 - (i + 2)
1 + 9i
Solve:
4x2 = 400
x = 10 and x = -10
Solve the system:
y = x2
y = 2x
x = 0 and x = 2
What is the quadratic formula?
Find the vertex:
f(x) = x2 - 8x + 15
(4, -1)
Multiply:
(8 - 3i)(8 + 3i)
73
Solve:
-x2 - 4x = 0
x = 0 and x = -4
How many solutions can a linear-quadratic system of equations have?
two real, one real, or no real solutions
Name FOUR methods to solve a quadratic equation.
Graphing
Factoring
Completing the Square
Quadratic Formula
Find the minimum point:
f(x) = 5x2 + 2x - 2
(-1/5, -11/5) or (-0.2, -2.2)
What are the solutions to
x2 + 2x + 8?
-1 +- i*sqrt(7)
Solve:
4x2 - 17x - 15 = 0
x = 5 and x = -3/4
Solve the system:
y = 2x2 - 6x - 8
2x - y = 16
x = 2
What room number are you in?
:)
A218
What feature of a graph does evaluating f(0) help you find?
Example: f(x) = 2x2 - 5x + 8
The y-intercept
Divide the expressions:
80/(2 - 6i)
4 + 12i
5x2 + 2x - 2
x = [-1 +- sqrt(11)] / 5
Solve the system:
3x2 - 7x + 4 = 9 - 2x
x = -0.70 and x = 2.37
Complete the square to write in vertex form:
f(x) = 4x2 + 8x - 5
f(x) = 4(x + 1)2 - 9