pre calc exam review: short answers Flashcards
What kind of symmetry do odd functions have?
Rotational about the origin
What is the vertical line test?
A way to determine whether the graph of an equation is a function y in terms of x
What kind of symmetry do even functions have?
Symmetry over the y axis
What is the equation of a vertical line?
X=2 (up and down)
What is the equation for a horizontal line?
Y=2 (left to right)
What is the slope of a vertical line?
Undefined– cannot have zero in the denominator, example: 3/0
What is the slope of a horizontal line?
0, because although you may be moving left or right, you’re not moving up or down, example: 0/3
What is the division algorithm?
F(X) = d (X) q (X) + r (X) Dividend = divisor X quotient plus remainder
What is the alternative to the division algorithm?
Dividend Remainder
——— = quotient + ———–
Divisor Divisor
When does a function have a minimum?
When A > 0
*use -b / 2a
When does a function have a maximum?
When A < 0
*use -b / 2a
For odd functions…
What do the left and right do as the leading coefficient is positive?
Left goes down and right goes up!
For odd functions…
What do the left and right do as the leading coefficient is negative?
Left goes up and right goes down!
For even functions…
What do the left and right do as the leading coefficient is positive?
Both go up!
For even functions…
What do the left and right do as the leading coefficient is negative?
Both go down!
What are logarithms?
The “opposite” of exponentials, just as subtraction is the opposite of addition and division is the opposite of multiplication. Logs “undo” exponentials. Technically speaking, logs are the inverses of exponentials.
What is the common log?
The logarithmic function with base 10 is called the common logarithmic function.
What is the natural log?
Is denoted by the special symbol ln x, read as “the natural log of x” or “el en of x.” The base is understood to be e.
What’s an inverse?
When the X and Y values are switched as well as the domains and ranges
What is the midpoint formula?
(X1+x2/2) (y1+y2/2)
Symmetry over the x axis becomes
(X, -y)
Symmetry over the y axis becomes
(-x, y)