Math Unit 3 Test Flashcards
Relation:
Relation: any relationship between two variables (ie. x and y)
Function:
Function: a special type of relation where each value of x corresponds with only one value of y. [ie. All values of x are unique]
All functions are ?, but not all relations are ?
Relations
Functions
Function: only ONE ? for each ?
y for each x
Relation: MULTIPLE ?’s for an ?
y’s for an x
Function: For every value of x there is only ? value of y. The x values are ? repeated Note: it does not matter the y values are repeated
One
Not
Relation: For the x value of -1, there are three values of y (4,6,7); therefore, it is ? a function. The x values of -1 is repeated
Not
Function: ? x values repeated
No
Relation: The x value 1 is ?
Repeated
To determine if a graph is the graph of a function, principle:
for every x value there should be only one y value.
Vertical Line Test:
if you draw an imaginary vertical through the graph at any position, it will only ever cross the relation once. If it crosses more than one time, it is not a function.
y = 3x - 1, ?, ?
Linear, Function
x^2 + y^2 = 25, ?, ?
Circle, Relation
y = -2x2 + 5x - 1, ?, ?
Quadratic, Function
Function Notation
sub the (x) in the equation for the x and wherever else x is
Domain -
all possible input values for the relation - the x values
Range -
all possible output values for the relation - the y values
{(-2, 2), (-3, 3), (-4, 4), (-3, 5), (-1, 6)} -
D: {-4,-3,-2,-1} R: {2, 3, 4, 5, 6}
If it’s a line -
D:{xER} R:{yER}
If it’s a parabola -
D:{xER} R:{yER l y≥?}
If it’s a circle -
D:{xER l ? ≥ x ≥ ? } R:{yER l ? ≥ y ≥ ? }
In (not function notation) y = a(x - h)^2 + k (a is…
the direction of opening, and vertical stretch/compression)
In (not function notation) y = a(x - h)^2 + k (h is…
a horizontal translation left or right)
In (not function notation) y = a(x - h)^2 + k (k is…
a vertical translation up or down
The “a” = Direction of Opening
a >0 parabola opens UP
a <0 parabola opens DOWN
The “a” = Stretch/Compression
- l a l >1 stretched by a factor ‘a’ (multiply y values by ‘a’)
- 0< l a l<1 compressed by a factor of ‘a’ (multiply y values by ‘a’)
The “h” = Horizontal Translation
(x-h)^2 translates ‘h’ units to the right
(x+h)^2 translates ‘h’ units to the left
The “k” = Vertical Translation
+k translates up ‘k’ units
-k translates down ‘k’ units
In (function notation) y = af [k (x - d)] + c (a is…
a = Direction of Opening (reflection of the x-axis) & Vertical Stretch/Compression