Vocabulary Flashcards
domain of a function
the input numbers, the x-values, domain of a function is all real numbers for which the equation produces outputs that are real numbers
range of function
the output values, the y-values or f(x) values
typically, a value of x that must be excluded from the domain of a function makes the denominator _____
zero
in place of an equation, a function with a small finite domain can also be described by _____
a set of ordered pairs
in a function, every x-value has _____ y-values
exactly one y-value. if an x-value has more than one y-value than it is not a function
relation
describes association between two variables. a function is a type of relation
in terms of functions and relations, a circle is ___
a relation that is not a function
relations that are not functions are ___
ellipses, hyperbolas, and parabolas that open side ways
combining functions f(x) and g(x)
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composition of functions f(x) and g(x)
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inverse of a function f, denoted by f^(-1)
switch y and x. putting y’s in place of the x’s and x’s in place of the y’s than solve for y
what is something to remember about inverses?
inverses don’t have to be a function
the graphs of inverses are ___
reflection of the original function about the line y=x
if the point with coordinates (a,b) belongs to a function f, then the point with coordinates ___ belongs to the inverse of f
(b,a)
the inverse of any function f can always be made a function by ___
limiting the domain of f. cutting out the parts that keep it from being a function
properties of an even function
f(x)=f(-x)
an even function is symmetric about the y-axis
properties of an odd function
f(-x) = -f(x), an odd function is symmetric about the origin
the sum of even functions is ___
even
the sum of odd functions is ___
odd
the product of an even function and an odd function is ___
odd
linear functions
polynomials in which the largest exponent is 1
graphs of linear equations are always a straight line
general form of the equation for a linear function
Ax + By + C = 0
- A/B = slope of line
- C/B = y intercept
slope intercept
y = mx + b m = slope of line b = y intercept
formula for slope
(y1 -y2)/(x1-x2)
point slope
y - y1 = m( x - x1 )
parallel lines have ___ slopes.
same
the slopes of 2 perpendicular lines are ___
negative reciprocals of one another
distance formula for x-y plane
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midpoint formula
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properties of quadratic functions
polynomials where the largest exponent is 2
graph is always a parabola
general form of equation for quadratic functions
y = ax^2 + bx + c
if a is positive, then graph opens up
if a is negative graph opens down
how to calculate x value of vertex of parabola
-b / 2a
zeroes of a quadratic function are ___
the points where the the graph crosses the x-axis, and y = 0
quadratic formula
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sum of the zeroes of a quadratic equations is ___
-b / a
determinant of a quadratic equation
(b^2) - 4ac
if determinant of quadratic equation equals 0
the two roots equal zero and the graph is tangent to the x-axis
if the determinant of quadratic equation is less than 0
the roots are two complex numbers because there is a negative under the radical and the graph never touches the x-axis
if the determinant of quadratic equation is more than zero
two different real roots and the graph intersects the x-axis in two places
the graphs of polynomial functions are always ________
continuous curves
if the largest exponent of a polynomial function is even then the ends of its graph
point in the same direction ( a parabola or a W)
if the largest exponent of a polynomial function is odd then the ends of its graph
point in opposite directions ( an S or snake graph)
if all the exponents of a polynomial function are even then the polynomial is an ______
even function and symmetric about the y-axis
if all the exponents of a polynomial function are odd then the polynomial is an _______________
odd function and symmetric about the origin
a polynomial of degree n has ___ zeroes
n, same number as degree
when it comes to the zeroes of polynomial functions, imaginary ezroes must ______
occur in pairs
with polynomial functions, real zeroes can occur ____
more than once
Remainder theorem
if a polynomial P(x) is divided by x-r (where r is any constant), then the remainder is P(r)
factor theorem
r is a zero of the polynomial P(x) if and only if x-r is a divisor of P(x)
rational zero (root) theorem
if p/q is a rational zero (reduced to lowest terms) of a polynomial P(x) with integral coefficients, then p is a factor of the constant term and q is is a factor of the leading coefficient
if P(x) is a polynomial with real coefficients, then complex zeroes occur as _____
conjugate pairs ( if p + qi is a zero then p - qi is also a zero)
angles measured in a counter clockwise direction from the initial side to the terminal side is said to have a _____ value
positive
angles measured in a clockwise direction from the initial side to the terminal side is said to have a _____ value
negative
sin and cos are always between ___ and ___
-1 and 1
the six trig definitions
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complimentary angles
add to 90 degrees
sumplementary angles
add to 180 degrees
cofunctions of complementary angles are ___
equal
if a and b are complimentary, then the sina=cosb
radian
the measure of one radius length
one radian equal 360/2pie
arc length equation
radius times angle (in radians)
area of a sector of a circle
(1/2)(radius ^2)( angle in radians)
special triangles
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periodic functions
where the values eventually repeat over regular intervals
period
smallest positive value in which a periodic function repeats
periods of six trig functions
sin, cos, csc, sec have periods of 2pie
tan and cot have periods of pie
the vertical asymptotes of sec, csc, tan and cot
sec and tan’s occur on pie/2
csc and cot’s occur on pie
general form of a trig function
y = A * trig(Bx + C) + D
amplitude = abs(A)
horizontal translation is -C/B and is called phase shift
period is period of original trig func divided by B
D is amount of vertical translation
reciprocal identities
csc = 1/sin sec = 1/cos cot = 1/ tan
cofunction identities
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pythagorean identities
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double angle formulas
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law of sines
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