Chpt. 4, Quadratics Flashcards
parabola
The graph of a quadratic function. It is the set of all points P in a plane that are the same distance from a fixed point F, as they are from a line d, the directrix.
quadratic function
A function that has a variable raised to the second degree. It can be written in the form f(x) = ax^2 +bx +c, where a does not equal zero.
vertex form of a quadratic function
F(x) = (x -h)^2 +k, where a does not equal zero, and where (h, k) are the coordinates for the vertex of the function.
axis of symmetry
The line that divides a figure into two parts that are mirror images of each other.
vertex of a parabola
The point where the function of the parabola reaches a maximum or minimum value. The parabola intersects it’s axis of symmetry at the vertex.
minimum value
The minimum value of a function y = f(x) is the least y-value of the function. It is the y-coordinate of the lowest value on the graph of f.
maximum value
The maximum value of a function y = f(x) is the greatest y-value of the function. It is the y-coordinate of the highest point on the graph of f.
exponential function transformations, from parent:
f(x) = x^2
to:
- stretch
- compression
- reflection in x-axis
- horizontal translation
- vertical translation
- all transformations combined
- f(x) = ax^2, when a > 1
2. f(x) = ax^2, when 0
The form ax^2 +bx +c, where a does not equal zero, is referred to as what?
standard form
What is the y-value of the vertex of any quadratic function that is written in standard form?
f ( -b/2a )
What three points on the graph of a quadratic function.
Three noncollinear points, no two of which are in a line vertically, are on the graph of exactly one quadratic function.
factoring
Re-writing an expression as the product of its factors.
greatest common factor (GCF)
The common factor of each term of an expression that has the greatest coefficient and the greatest exponent.
perfect square trinomial
A trinomial that is the square of a binomial.
Example:
Binomial Square = (4x - 3)^2
Trinomial = 16x^2 -24x +9
difference of two squares
An expression of the form a^2 - b^2. It can be factored in the form (a + b)(a - b).