- absolute convergence
- if the series ∞∑n=1|an|∞∑n=1|an| converges, the series ∞∑n=1an∞∑n=1an is said to converge absolutely
- absolute error
- if BB is an estimate of some quantity having an actual value of AA, then the absolute error is given by |A−B||A−B|
- alternating series
- a series of the form ∞∑n=1(−1)n+1bn∞∑n=1(−1)n+1bn or ∞∑n=1(−1)nbn∞∑n=1(−1)nbn, where bn≥0bn≥0, is called an alternating series
- alternating series test
- for an alternating series of either form, if bn+1≤bnbn+1≤bn for all integers n≥1n≥1 and bn→0bn→0, then an alternating series converges
- angular coordinate
- θθ the angle formed by a line segment connecting the origin to a point in the polar coordinate system with the positive radial (x) axis, measured counterclockwise
- arc length
- the arc length of a curve can be thought of as the distance a person would travel along the path of the curve
- arithmetic sequence
- a sequence in which the difference between every pair of consecutive terms is the same is called an arithmetic sequence
- asymptotically semi-stable solution
- y=ky=k if it is neither asymptotically stable nor asymptotically unstable
- asymptotically stable solution
- y=ky=k if there exists ϵ>0ϵ>0 such that for any value c∈(k−ϵ,k+ϵ)c∈(k−ϵ,k+ϵ) the solution to the initial-value problem y′=f(x,y),y(x0)=c approaches k as x approaches infinity
- asymptotically unstable solution
- y=k if there exists ϵ>0 such that for any value c∈(k−ϵ,k+ϵ) the solution to the initial-value problem y′=f(x,y),y(x0)=c never approaches k as x approaches infinity
- autonomous differential equation
- an equation in which the right-hand side is a function of y alone
- average value of a function
- (or fave) the average value of a function on an interval can be found by calculating the definite integral of the function and dividing that value by the length of the interval
- binomial series
- the Maclaurin series for f(x)=(1+x)r; it is given by
(1+x)r=∞∑n=0(rn)xn=1+rx+r(r−1)2!x2+⋯+r(r−1)⋯(r−n+1)n!xn+⋯ for |x|<1
- bounded above
- a sequence {an} is bounded above if there exists a constant M such that an≤M for all positive integers n
- bounded below
- a sequence {an} is bounded below if there exists a constant M such that M≤an for all positive integers n
- bounded sequence
- a sequence {an} is bounded if there exists a constant M such that |an|≤M for all positive integers n
- cardioid
- a plane curve traced by a point on the perimeter of a circle that is rolling around a fixed circle of the same radius; the equation of a cardioid is r=a(1+sinθ) or r=a(1+cosθ)
- carrying capacity
- the maximum population of an organism that the environment can sustain indefinitely
- catenary
- a curve in the shape of the function y=acosh(x/a) is a catenary; a cable of uniform density suspended between two supports assumes the shape of a catenary
- center of mass
- the point at which the total mass of the system could be concentrated without changing the moment
- centroid
- the centroid of a region is the geometric center of the region; laminas are often represented by regions in the plane; if the lamina has a constant density, the center of mass of the lamina depends only on the shape of the corresponding planar region; in this case, the center of mass of the lamina corresponds to the centroid of the representative region
- change of variables
- the substitution of a variable, such as u, for an expression in the integrand
- comparison test
- if 0≤an≤bn for all n≥N and ∞∑n=1bn converges, then ∞∑n=1an converges; if an≥bn≥0 for all n≥N and ∞∑n=1bn diverges, then ∞∑n=1an diverges
- computer algebra system (CAS)
- technology used to perform many mathematical tasks, including integration
- conditional convergence
- if the series ∞∑n=1an converges, but the series ∞∑n=1|an| diverges, the series ∞∑n=1an is said to converge conditionally
- conic section
- a conic section is any curve formed by the intersection of a plane with a cone of two nappes
- convergence of a series
- a series converges if the sequence of partial sums for that series converges
- convergent sequence
- a convergent sequence is a sequence {an} for which there exists a real number L such that an is arbitrarily close to L as long as n is sufficiently large
- cross-section
- the intersection of a plane and a solid object
- cusp
- a pointed end or part where two curves meet
- cycloid
- the curve traced by a point on the rim of a circular wheel as the wheel rolls along a straight line without slippage
- definite integral
- a primary operation of calculus; the area between the curve and the x-axis over a given interval is a definite integral
- density function
- a density function describes how mass is distributed throughout an object; it can be a linear density, expressed in terms of mass per unit length; an area density, expressed in terms of mass per unit area; or a volume density, expressed in terms of mass per unit volume; weight-density is also used to describe weight (rather than mass) per unit volume
- differential equation
- an equation involving a function y=y(x) and one or more of its derivatives
- direction field (slope field)
- a mathematical object used to graphically represent solutions to a first-order differential equation; at each point in a direction field, a line segment appears whose slope is equal to the slope of a solution to the differential equation passing through that point
- directrix
- a directrix (plural: directrices) is a line used to construct and define a conic section; a parabola has one directrix; ellipses and hyperbolas have two
- discriminant
- the value 4AC−B2, which is used to identify a conic when the equation contains a term involving xy, is called a discriminant
- disk method
- a special case of the slicing method used with solids of revolution when the slices are disks
- divergence of a series
- a series diverges if the sequence of partial sums for that series diverges
- divergence test
- if limn→∞an≠0, then the series ∞∑n=1an diverges
- divergent sequence
- a sequence that is not convergent is divergent
- doubling time
- if a quantity grows exponentially, the doubling time is the amount of time it takes the quantity to double, and is given by (ln2)k
- eccentricity
- the eccentricity is defined as the distance from any point on the conic section to its focus divided by the perpendicular distance from that point to the nearest directrix
- equilibrium solution
- any solution to the differential equation of the form y=c, where c is a constant
- Euler’s Method
- a numerical technique used to approximate solutions to an initial-value problem
- explicit formula
- a sequence may be defined by an explicit formula such that an=f(n)
- exponential decay
- systems that exhibit exponential decay follow a model of the form y=y0e−kt
- exponential growth
- systems that exhibit exponential growth follow a model of the form y=y0ekt
- focal parameter
- the focal parameter is the distance from a focus of a conic section to the nearest directrix
- focus
- a focus (plural: foci) is a point used to construct and define a conic section; a parabola has one focus; an ellipse and a hyperbola have two
- frustum
- a portion of a cone; a frustum is constructed by cutting the cone with a plane parallel to the base
- fundamental theorem of calculus
- the theorem, central to the entire development of calculus, that establishes the relationship between differentiation and integration
- fundamental theorem of calculus, part 1
- uses a definite integral to define an antiderivative of a function
- fundamental theorem of calculus, part 2
- (also, evaluation theorem) we can evaluate a definite integral by evaluating the antiderivative of the integrand at the endpoints of the interval and subtracting
- general form
- an equation of a conic section written as a general second-degree equation
- general solution (or family of solutions)
- the entire set of solutions to a given differential equation
- geometric sequence
- a sequence {an} in which the ratio an+1an is the same for all positive integers n is called a geometric sequence
- geometric series
- a geometric series is a series that can be written in the form
∞∑n=1arn−1=a+ar+ar2+ar3+⋯
- growth rate
- the constant r>0 in the exponential growth function P(t)=P0ert
- half-life
- if a quantity decays exponentially, the half-life is the amount of time it takes the quantity to be reduced by half. It is given by (ln2)k
- harmonic series
- the harmonic series takes the form
∞∑n=11n=1+12+13+⋯
- Hooke’s law
- this law states that the force required to compress (or elongate) a spring is proportional to the distance the spring has been compressed (or stretched) from equilibrium; in other words, F=kx, where k is a constant
- hydrostatic pressure
- the pressure exerted by water on a submerged object
- improper integral
- an integral over an infinite interval or an integral of a function containing an infinite discontinuity on the interval; an improper integral is defined in terms of a limit. The improper integral converges if this limit is a finite real number; otherwise, the improper integral diverges
- index variable
- the subscript used to define the terms in a sequence is called the index
- infinite series
- an infinite series is an expression of the form
a1+a2+a3+⋯=∞∑n=1an
- initial population
- the population at time t=0
- initial value(s)
- a value or set of values that a solution of a differential equation satisfies for a fixed value of the independent variable
- initial velocity
- the velocity at time t=0
- initial-value problem
- a differential equation together with an initial value or values
- integrable function
- a function is integrable if the limit defining the integral exists; in other words, if the limit of the Riemann sums as n goes to infinity exists
- integral test
- for a series ∞∑n=1an with positive terms an, if there exists a continuous, decreasing function f such that f(n)=an for all positive integers n, then
∞∑n=1an and ∫∞1f(x)dxeither both converge or both diverge
- integrand
- the function to the right of the integration symbol; the integrand includes the function being integrated
- integrating factor
- any function f(x) that is multiplied on both sides of a differential equation to make the side involving the unknown function equal to the derivative of a product of two functions
- integration by parts
- a technique of integration that allows the exchange of one integral for another using the formula ∫udv=uv−∫vdu
- integration by substitution
- a technique for integration that allows integration of functions that are the result of a chain-rule derivative
- integration table
- a table that lists integration formulas
- interval of convergence
- the set of real numbers x for which a power series converges
- lamina
- a thin sheet of material; laminas are thin enough that, for mathematical purposes, they can be treated as if they are two-dimensional
- left-endpoint approximation
- an approximation of the area under a curve computed by using the left endpoint of each subinterval to calculate the height of the vertical sides of each rectangle
- limaçon
- the graph of the equation r=a+bsinθ or r=a+bcosθ. If a=b then the graph is a cardioid
- limit comparison test
- suppose an,bn≥0 for all n≥1. If limn→∞anbn→L≠0, then ∞∑n=1an and ∞∑n=1bn both converge or both diverge; if limn→∞anbn→0 and ∞∑n=1bn converges, then ∞∑n=1an converges. If limn→∞anbn→∞, and ∞∑n=1bn diverges, then ∞∑n=1an diverges
- limit of a sequence
- the real number L to which a sequence converges is called the limit of the sequence
- limits of integration
- these values appear near the top and bottom of the integral sign and define the interval over which the function should be integrated
- linear
- description of a first-order differential equation that can be written in the form a(x)y′+b(x)y=c(x)
- logistic differential equation
- a differential equation that incorporates the carrying capacity K and growth rate r into a population model
- lower sum
- a sum obtained by using the minimum value of f(x) on each subinterval
- Maclaurin polynomial
- a Taylor polynomial centered at 0; the nth Taylor polynomial for f at 0 is the nth Maclaurin polynomial for f
- Maclaurin series
- a Taylor series for a function f at x=0 is known as a Maclaurin series for f
- major axis
- the major axis of a conic section passes through the vertex in the case of a parabola or through the two vertices in the case of an ellipse or hyperbola; it is also an axis of symmetry of the conic; also called the transverse axis
- mean value theorem for integrals
- guarantees that a point c exists such that f(c) is equal to the average value of the function
- method of cylindrical shells
- a method of calculating the volume of a solid of revolution by dividing the solid into nested cylindrical shells; this method is different from the methods of disks or washers in that we integrate with respect to the opposite variable
- midpoint rule
- a rule that uses a Riemann sum of the form Mn=n∑i=1f(mi)Δx, where mi is the midpoint of the ith subinterval to approximate ∫baf(x)dx
- minor axis
- the minor axis is perpendicular to the major axis and intersects the major axis at the center of the conic, or at the vertex in the case of the parabola; also called the conjugate axis
- moment
- if n masses are arranged on a number line, the moment of the system with respect to the origin is given by M=∑i=1nmixi; if, instead, we consider a region in the plane, bounded above by a function f(x) over an interval [a,b], then the moments of the region with respect to the x– and y-axes are given by Mx=ρ∫ba[f(x)]22dx and My=ρ∫baxf(x)dx, respectively
- monotone sequence
- an increasing or decreasing sequence
- nappe
- a nappe is one half of a double cone
- net change theorem
- if we know the rate of change of a quantity, the net change theorem says the future quantity is equal to the initial quantity plus the integral of the rate of change of the quantity
- net signed area
- the area between a function and the x-axis such that the area below the x-axis is subtracted from the area above the x-axis; the result is the same as the definite integral of the function
- nonelementary integral
- an integral for which the antiderivative of the integrand cannot be expressed as an elementary function
- numerical integration
- the variety of numerical methods used to estimate the value of a definite integral, including the midpoint rule, trapezoidal rule, and Simpson’s rule
- order of a differential equation
- the highest order of any derivative of the unknown function that appears in the equation
- orientation
- the direction that a point moves on a graph as the parameter increases
- p-series
- a series of the form ∞∑n=11np
- parameter
- an independent variable that both x and y depend on in a parametric curve; usually represented by the variable t
- parametric curve
- the graph of the parametric equations x(t) and y(t) over an interval a≤t≤b combined with the equations
- parametric equations
- the equations x=x(t) and y=y(t) that define a parametric curve
- parameterization of a curve
- rewriting the equation of a curve defined by a function y=f(x) as parametric equations
- partial fraction decomposition
- a technique used to break down a rational function into the sum of simple rational functions
- partial sum
- the kth partial sum of the infinite series ∞∑n=1an is the finite sum
Sk=k∑n=1an=a1+a2+a3+⋯+ak
- particular solution
- member of a family of solutions to a differential equation that satisfies a particular initial condition
- partition
- a set of points that divides an interval into subintervals
- phase line
- a visual representation of the behavior of solutions to an autonomous differential equation subject to various initial conditions
- polar axis
- the horizontal axis in the polar coordinate system corresponding to r≥0
- polar coordinate system
- a system for locating points in the plane. The coordinates are r, the radial coordinate, and θ, the angular coordinate
- polar equation
- an equation or function relating the radial coordinate to the angular coordinate in the polar coordinate system
- pole
- the central point of the polar coordinate system, equivalent to the origin of a Cartesian system
- power reduction formula
- a rule that allows an integral of a power of a trigonometric function to be exchanged for an integral involving a lower power
- power series
- a series of the form ∞∑n=0cnxn is a power series centered at x=0; a series of the form ∞∑n=0cn(x−a)n is a power series centered at x=a
- radial coordinate
- r the coordinate in the polar coordinate system that measures the distance from a point in the plane to the pole
- radius of convergence
- if there exists a real number R>0 such that a power series centered at x=a converges for [latex]|x-a|
R[/latex], then R is the radius of convergence; if the power series only converges at x=a, the radius of convergence is R=0; if the power series converges for all real numbers x, the radius of convergence is R=∞
- ratio test
- for a series ∞∑n=1an with nonzero terms, let ρ=limn→∞|an+1an|; if 0≤ρ<1, the series converges absolutely; if ρ>1, the series diverges; if ρ=1, the test is inconclusive
- recurrence relation
- a recurrence relation is a relationship in which a term an in a sequence is defined in terms of earlier terms in the sequence
- regular partition
- a partition in which the subintervals all have the same width
- relative error
- error as a percentage of the absolute value, given by |A−BA|=|A−BA|⋅100%
- remainder estimate
- for a series ∞∑n=1an with positive terms an and a continuous, decreasing function f such that f(n)=an for all positive integers n, the remainder RN=∞∑n=1an−N∑n=1an satisfies the following estimate:
∫∞N+1f(x)dx<RN<∫∞Nf(x)dx
- riemann sum
- an estimate of the area under the curve of the form A≈nΣi=1f(x∗i)Δx
- right-endpoint approximation
- the right-endpoint approximation is an approximation of the area of the rectangles under a curve using the right endpoint of each subinterval to construct the vertical sides of each rectangle
- root test
- for a series ∞∑n=1an, let ρ=limn→∞n√|an|; if 0≤ρ<1, the series converges absolutely; if ρ>1, the series diverges; if ρ=1, the test is inconclusive
- rose
- graph of the polar equation r=acosnθ or r=asinnθ for a positive constant a and an integer n≥2
- separable differential equation
- any equation that can be written in the form y′=f(x)g(y)
- separation of variables
- a method used to solve a separable differential equation
- sequence
- an ordered list of numbers of the form a1,a2,a3,… is a sequence
- sigma notation
- (also, summation notation) the Greek letter sigma (Σ) indicates addition of the values; the values of the index above and below the sigma indicate where to begin the summation and where to end it
- Simpson’s rule
- a rule that approximates ∫baf(x)dx using the integrals of a piecewise quadratic function. The approximation Sn to ∫baf(x)dx is given by Sn=Δx3(f(x0)+4f(x1)+2f(x2)+4f(x3)+2f(x4)+4f(x5)+⋯+2f(xn−2)+4f(xn−1)+f(xn)) trapezoidal rule a rule that approximates ∫baf(x)dx using trapezoids
- slicing method
- a method of calculating the volume of a solid that involves cutting the solid into pieces, estimating the volume of each piece, then adding these estimates to arrive at an estimate of the total volume; as the number of slices goes to infinity, this estimate becomes an integral that gives the exact value of the volume
- solid of revolution
- a solid generated by revolving a region in a plane around a line in that plane
- solution curve
- a curve graphed in a direction field that corresponds to the solution to the initial-value problem passing through a given point in the direction field
- solution to a differential equation
- a function y=f(x) that satisfies a given differential equation
- space-filling curve
- a curve that completely occupies a two-dimensional subset of the real plane
- standard form
- the form of a first-order linear differential equation obtained by writing the differential equation in the form y′+p(x)y=q(x)
- standard form
- an equation of a conic section showing its properties, such as location of the vertex or lengths of major and minor axes
- step size
- the increment h that is added to the x value at each step in Euler’s Method
- surface area
- the surface area of a solid is the total area of the outer layer of the object; for objects such as cubes or bricks, the surface area of the object is the sum of the areas of all of its faces
- symmetry principle
- the symmetry principle states that if a region R is symmetric about a line l, then the centroid of R lies on l
- Taylor polynomials
- the nth Taylor polynomial for f at x=a is pn(x)=f(a)+f′(a)(x−a)+f′′(a)2!(x−a)2+⋯+f(n)(a)n!(x−a)n
- Taylor series
- a power series at a that converges to a function f on some open interval containing a
- Taylor’s theorem with remainder
- for a function f and the nth Taylor polynomial for f at x=a, the remainder Rn(x)=f(x)−pn(x) satisfies Rn(x)=f(n+1)(c)(n+1)!(x−a)n+1
for some c between x and a; if there exists an interval I containing a and a real number M such that |f(n+1)(x)|≤M for all x in I, then |Rn(x)|≤M(n+1)!|x−a|n+1
- telescoping series
- a telescoping series is one in which most of the terms cancel in each of the partial sums
- term
- the number an in the sequence {an} is called the nth term of the sequence
- term-by-term differentiation of a power series
- a technique for evaluating the derivative of a power series ∞∑n=0cn(x−a)n by evaluating the derivative of each term separately to create the new power series ∞∑n=1ncn(x−a)n−1
- term-by-term integration of a power series
- a technique for integrating a power series ∞∑n=0cn(x−a)n by integrating each term separately to create the new power series C+∞∑n=0cn(x−a)n+1n+1
- theorem of Pappus for volume
- this theorem states that the volume of a solid of revolution formed by revolving a region around an external axis is equal to the area of the region multiplied by the distance traveled by the centroid of the region
- threshold population
- the minimum population that is necessary for a species to survive
- total area
- total area between a function and the x-axis is calculated by adding the area above the x-axis and the area below the x-axis; the result is the same as the definite integral of the absolute value of the function
- trigonometric integral
- an integral involving powers and products of trigonometric functions
- trigonometric substitution
- an integration technique that converts an algebraic integral containing expressions of the form √a2−x2, √a2+x2, or √x2−a2 into a trigonometric integral
- unbounded sequence
- a sequence that is not bounded is called unbounded
- upper sum
- a sum obtained by using the maximum value of f(x) on each subinterval
- variable of integration
- indicates which variable you are integrating with respect to; if it is x, then the function in the integrand is followed by dx
- vertex
- a vertex is an extreme point on a conic section; a parabola has one vertex at its turning point. An ellipse has two vertices, one at each end of the major axis; a hyperbola has two vertices, one at the turning point of each branch
- washer method
- a special case of the slicing method used with solids of revolution when the slices are washers
- work
- the amount of energy it takes to move an object; in physics, when a force is constant, work is expressed as the product of force and distance