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  • erplex

    Concept Lessons

    Access comprehensive explorations for all concepts in your objective, including problems, helpful visuals, and AI features.

    What you'll find in every lesson:

    High-quality explanations: Each lesson is carefully crafted to help you truly understand the concept, not just memorize it.

    Checkpoint exercises: Practice as you learn with interactive problems designed to reinforce your understanding.

    AI-powered discussions: Engage with thought-provoking questions that help reveal your misconceptions.

    What you'll find in every lesson:

    High-quality explanations: Each lesson is carefully crafted to help you truly understand the concept, not just memorize it.

    Checkpoint exercises: Practice as you learn with interactive problems designed to reinforce your understanding.

    AI-powered discussions: Engage with thought-provoking questions that help reveal your misconceptions.

    Concept Lessons

    Access comprehensive explorations for all concepts in your objective, including problems, helpful visuals, and AI features.

    51 Lessons Available

    What you'll find in every lesson:

    High-quality explanations: Each lesson is carefully crafted to help you truly understand the concept, not just memorize it.

    Checkpoint exercises: Practice as you learn with interactive problems designed to reinforce your understanding.

    AI-powered discussions: Engage with thought-provoking questions that help reveal your misconceptions.

    What you'll find in every lesson:

    High-quality explanations: Each lesson is carefully crafted to help you truly understand the concept, not just memorize it.

    Checkpoint exercises: Practice as you learn with interactive problems designed to reinforce your understanding.

    AI-powered discussions: Engage with thought-provoking questions that help reveal your misconceptions.

    Approximations & Error

    2 concepts with notes

    Rounding Numbers

    Rounding, significant figures, decimal places

    Scientific Notation

    Converting numbers to and from scientific notation (a×10k)

    Differentiation

    6 concepts with notes

    Limits and Derivatives

    The concept (and basic properties) of limits and derivatives

    Differentiation rules

    Power rule, chain rule, product rule, quotient rule, derivatives of ex, ax, loga​(x), trigonometric, and inverse trigonometric functions

    Tangents and normals

    Definitions of tangent and normal, finding tangent and normal lines to a function

    Applications of the First Derivative

    Increasing and decreasing intervals, stationary points (maxima and minima), and optimisation

    Second Derivatives and Applications

    Definition of the second derivative, concavity, inflexion points

    n^th Derivative

    Taking the nth derivative, inductive proofs with the nth derivative

    Integration

    4 concepts with notes

    Definite Integrals, Areas, and Basic Anti-Derivatives

    Concept of an integral, areas with definite integrals, and basic anti-derivative solving skills

    Anti-Derivative Rules

    Antiderivatives of polynomials, trigonometric, inverse trigonometric, exponential, and logarithmic functions

    Techniques of Integration

    The reverse chain rule, integration by substitution, integration by parts, additional strategies

    Kinematics

    Computations involving distance, displacement, velocity, and acceleration

    Exponents & Logarithms

    4 concepts with notes

    Exponential Algebra

    Exponents, properties of exponents, and solving exponential equations

    Logarithm algebra

    Definition and evaluation of logarithms, properties of logs, e and the natural log, change of base rule

    Radicals and Roots

    Nth roots, fractional and rational exponents, conjugates

    Exp & Log functions

    Graphing exponential functions, Exponential growth and decay, logarithmic inverse functions

    Sequences & Series

    7 concepts with notes

    Arithmetic Sequences

    Introduction to the definition, properties, and general term of an arithmetic sequence

    Geometric Sequences

    Introduction to definition, identification, and general term of geometric sequences

    Arithmetic Series

    Definition of series, formula for arithmetic series

    Σ summation notation

    Summation notation, properties of sums

    Geometric Series

    Definition and general term of geometric series, finite and infinite series, convergence

    Sequence Mode (Calculator)

    Working with sequences on a calculator, computations and applications of a calculator

    Compounding (Appreciation & Depreciation)

    Compound growth, depreciation, interest, inflation, real value

    Descriptive Statistics

    1 concept with notes

    Linear Regression

    Regressions of y on x, regressions of x on y, the correlation coefficient r, the rank correlation coefficient rs​, extrapolation and interpolation of data

    Probability

    4 concepts with notes

    Probabilistic Events

    Theoretical and experimental probability, complementary events, expected number of outcomes, sample space

    Combined Events

    Venn diagrams, intersection and union of events, conditional probability, independent events

    Dependence

    Tree diagrams, selection with/without replacement, dependence

    Bayes' Theorem

    Bayes' theorem with 2 and 3 events, sum of conditional probabilities

    Cartesian plane & lines

    3 concepts with notes

    Distance, Midpoint, & Gradient

    Distance between two points, midpoint of two points, and finding gradient using two points

    Equations of a Line

    Gradient-intercept form, point-gradient form, vertical lines, horizontal lines, standard form of a line

    Line Intersections & Systems of Equations

    Parallel and perpendicular lines, intersection of 2 straight lines, solving a two-variable system of equations

    Quadratics

    2 concepts with notes

    Foundations of Quadratics

    Vertex, standard, and factored form, axis of symmetry, concavity, quadratic formula

    Applications of Quadratics

    Evaluating the discriminant, sum and product of roots, quadratic inequalities, quadratics of other forms

    Function Theory

    3 concepts with notes

    Function Graphs

    Graphing functions with a calculator, characteristics of a function, even and odd functions, x and y intercepts, horizontal and vertical asymptotes, maxima and minima

    Function Composition & Inverses

    Composing functions, inverse functions, graphing and evaluating inverse functions, computing inverses and domain restrictions

    Functions and their properties

    Domain and range of functions, function as a model, interval notation

    Transformations & asymptotes

    2 concepts with notes

    Linear Transformations

    Vertical and horizontal translations, dilations, reflecting over axes

    Rational functions

    Reciprocal functions, quadratic denominators, graphs of rational linear functions

    Distributions & Random Variables

    3 concepts with notes

    Discrete random variables

    Introduction and properties of random variables, probability distributions, expected value and variance, linear transformations of r.v.'s

    Binomial Distribution

    Concept of the binomial distribution, binomial PDF and CDF, expectation and variance of binomial distribution

    Normal Distribution

    Introduction and definition of the normal distribution, standard deviations, normal and inverse normal calculations, z-values, normal standardization

    Trig equations & identities

    5 concepts with notes

    The Unit Circle

    Sine, cosine & tangent functions in the unit circle

    Reciprocal trig functions

    The functions secx, cosecx and cotx, domain, range & graphs

    Trigonometric Functions

    Graphs, domain, and range of sinx and cosx, general sinusoidal functions, modeling periodic phenomena, tanx and reciprocal trig functions, inverse trig functions

    Trigonometric Identities

    Applications of trigonometric identities such as sin2θ+cos2θ=1, sin2θ=2sinθcosθ and more identities for HL students

    Trig Equations

    Solving equations involving trigonometric functions and understanding solution domains

    2D & 3D Geometry

    5 concepts with notes

    Right angled triangles

    Pythagoras's theorem, SOHCAHTOA, finding side length from angles

    Non-right-angled triangles

    Sine and cosine rules, finding general area of a triangle

    Applied triangle geometry

    Angles of elevation and depression, true bearings, projections and more

    Circles: Radians, arcs and sectors

    Measuring angles in radians, circumference & arc lengths and sector areas

    3D solids

    Spheres, cylinders, prisms, right cones, right pyramids, and combinations of solids