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Subtraction Property of Equality - Definition & Examples
Log Table: How to Read & Use a Logarithm Table
Algebra 2: Topics, Concepts & How They Connect
Constants in Math: Definition, Examples & Types
Absolute Value: Definition, Symbol, Graph & Examples
Periodic Function: Definition, Formula, Graph & Examples
Parabolic Function — Definition, Formula, Graph, and Examples
Into Function — Definition, Graph, and Examples (Into vs Onto)
Identity Function — Definition, Graph, Properties, and Examples
Inverse Relation - Definition, Formula & Examples
Discontinuous Function - Types, Graph & Examples
Substitution Property of Equality - Definition & Examples
Sum of an Infinite GP - Formula & Examples
Sum of a GP - Formula, Derivation & Examples
Cramer's Rule - Formula, 2x2 & 3x3 Examples
Elimination Method — Steps and Worked Examples
Subtraction Property of Equality - Definition & Examples
Log Table: How to Read & Use a Logarithm Table
Algebra 2: Topics, Concepts & How They Connect
Constants in Math: Definition, Examples & Types
Absolute Value: Definition, Symbol, Graph & Examples
Periodic Function: Definition, Formula, Graph & Examples
Parabolic Function — Definition, Formula, Graph, and Examples
Into Function — Definition, Graph, and Examples (Into vs Onto)
Identity Function — Definition, Graph, Properties, and Examples
Inverse Relation - Definition, Formula & Examples
Discontinuous Function - Types, Graph & Examples
Substitution Property of Equality - Definition & Examples
Sum of an Infinite GP - Formula & Examples
Sum of a GP - Formula, Derivation & Examples
Cramer's Rule - Formula, 2x2 & 3x3 Examples
Elimination Method — Steps and Worked Examples
The goal was never to make kids faster at math — it was to make them fall in love with it. Speed is a byproduct of genuine understanding.
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Algebra
Variables, equations, and the language of math
Subtraction Property of Equality - Definition & Examples
The subtraction property of equality states that if , then - subtracting the same number from both sides of an equation keeps it balanced. It is the rule that lets you isolate a variable by stripping away an added term. This article gives the formula, works six examples including fractions and a two-column proof step, and shows how this property and the addition property are two halves of the same balance principle.
Log Table: How to Read & Use a Logarithm Table
A log table is a reference chart that gives the base-10 logarithm of a number, used to multiply, divide, and find powers by hand. To read a value, you split the logarithm into two parts: the characteristic (the integer part) and the mantissa (the decimal part, read from the table).
Algebra 2: Topics, Concepts & How They Connect
Algebra 2 is the high-school course that extends Algebra 1 into the full world of functions (polynomial, rational, radical, exponential, logarithmic, and trigonometric) and adds matrices, sequences, and conic sections. The thread tying Algebra 2 together is the idea of a function: a rule that takes an input and returns a single output.
Geometry
Shapes, proofs, and spatial thinking
Types of Angles — Acute, Right, Obtuse, Reflex
An acute angle measures between and — but it is only one of five named angle types. This article gives a complete reference table for all five (acute, right, obtuse, straight, reflex), with definitions, diagrams, real-world examples, and the common mistakes students make when sorting them.
60 Degrees to Radians — Value, Formula, and Examples
60 degrees equals radians, approximately 1.0472. This article shows the conversion formula (multiply degrees by ), a quick reference table of common angles, where turns up, the step-by-step method, and the mistakes to avoid.
Projection Vector — Formula, Derivation, and Examples
The projection vector of onto is the "shadow" casts along the direction of , given by . This article covers the projection formula and its derivation, the difference between scalar and vector projection, what a negative projection means, and worked examples.
Trigonometry
Angles, waves, and circular harmony
Cos 2pi/3 = −1/2 — Value of cos(2π/3) on Unit Circle
The value of cos 2pi/3 is exactly , which is . In degrees, is , an angle in the second quadrant where cosine is negative. This article shows why on the unit circle, gives a standard-angle reference table in radians and degrees, and clears up the sign slip students hit most.
Cos 2pi = 1 — Value of cos(2π) on the Unit Circle
The value of cos 2pi is exactly . A full rotation of radians (that is ) returns to the starting point, so . This article shows why one complete trip around the unit circle brings cosine back to , gives a standard-angle reference table in radians and degrees, and clears up the slips students hit most.
Cos 270 Degrees = 0 — Value, Unit Circle, Radians
The value of cos 270 degrees is exactly . In radians, is , so . This article shows why three-quarters of a turn lands on the bottom of the unit circle where the -coordinate vanishes, gives a standard-angle reference table in degrees and radians, and clears up the common mix-ups.
Parenting
Raising confident, curious young mathematicians
Math Formulas
Every essential formula, explained and derived
Maths Formulas for Class 10 — Chapter-Wise List
The maths formulas for class 10 span the full board syllabus — real numbers, polynomials, linear and quadratic equations, arithmetic progressions, triangles, coordinate geometry, trigonometry, circles, mensuration, statistics, and probability. This hub lists every formula by chapter, explains where each one comes from, and works one example per cluster so the formulas connect instead of floating loose.
nPr Formula — Permutations, Derivation, Examples
The nPr formula counts how many ordered arrangements of objects you can make from distinct objects: . This article derives that formula from the counting principle, defines every symbol, shows where order makes a permutation different from a combination, and works six examples from a simple line-up to a locked-position arrangement.
Sum of Arithmetic Sequence Formula — Proof, Examples
The sum of arithmetic sequence formula adds the first terms of an arithmetic progression: . This article derives both forms by the pairing trick, defines every variable, works through six examples from one-step sums to finding from a known total, and clears up the mistakes that cost the most marks.
Math Terms
Crystal-clear definitions with worked examples
CP Formula — How to Find Cost Price, Examples
The CP formula recovers the cost price of an item from its selling price and a profit or loss: , , and from a percentage, or . This article derives all four forms, defines every term, and works six examples plus the percentage mistakes that flip answers.
Isosceles Triangle Formula — Area, Perimeter, Height
The isosceles triangle formula set is: area (or from the equal side and base ), perimeter , and height . This article gives each formula, derives the height and area straight from the Pythagorean theorem, works six examples from one-step to a word problem, and clears up the mistakes that cost the most marks.
What Is a Chord? Definition, Properties & Examples
A chord is a straight line segment whose two endpoints both lie on a curve — most often a circle. This article defines the term, gives the chord-length formulas, lays out the key chord properties, works six examples, and clears up the chord-versus-diameter mix-up that trips students.
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