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Algebra 2 Class Online For Kids
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Mental Maths for Grade 5: Live Online Classes
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Zeros of a Cubic Polynomial - Sum, Product, Roots
Types of Relations - Reflexive, Symmetric, Transitive
Sum of N Terms of an AP - Formula, Derivation, and Examples
Subtraction of Matrices - Rules, Properties, and Examples
Square Root Tricks - Fast Methods & Examples
Square Root of 9000 - How to Simplify and Find √9000?
Square Root of 6400 - Why It Equals 80
Square Root of 5000 - Value, Simplest Form, and Examples
Square Root of 4100 - Value, Simplest Form, and Examples
Square Root of 4000 - Value 20√10, Simplify, Examples
Square Root of 1681 - How to Find the Square Root of 1681?
Square Root of 1500 - How to Simplify √1500?
Algebra 2 Class Online For Kids
Algebra 2 Tutors for Kids Online
Mental Maths for Grade 5: Live Online Classes
Mental Maths for Grade 4: Live Online Classes
Zeros of a Cubic Polynomial - Sum, Product, Roots
Types of Relations - Reflexive, Symmetric, Transitive
Sum of N Terms of an AP - Formula, Derivation, and Examples
Subtraction of Matrices - Rules, Properties, and Examples
Square Root Tricks - Fast Methods & Examples
Square Root of 9000 - How to Simplify and Find √9000?
Square Root of 6400 - Why It Equals 80
Square Root of 5000 - Value, Simplest Form, and Examples
Square Root of 4100 - Value, Simplest Form, and Examples
Square Root of 4000 - Value 20√10, Simplify, Examples
Square Root of 1681 - How to Find the Square Root of 1681?
Square Root of 1500 - How to Simplify √1500?
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
Product of Vectors — Dot and Cross Product Guide
The product of vectors comes in two distinct forms: the dot product a · b = |a||b|cosθ, which returns a number, and the cross product a × b = |a||b|sinθ, n, which returns a vector. This article maps both, shows when each one is the right tool, and extends the idea to the scalar triple product.
Exponents — Definition, Laws, and Examples
An exponent tells you how many times to multiply a number, the base, by itself — so 2⁵ means 2 × 2 × 2 × 2 × 2 = 32. This article covers what an exponent is, the parts of a power, the seven laws of exponents at a glance, negative, fractional, zero, and decimal exponents, where exponents show up in the real world, and the slips that cost marks.
Matrix Scalar Multiplication - Rules, Properties, Examples
Matrix scalar multiplication means multiplying every entry of a matrix by a single number called a scalar — if A = [a ij ] and k is a scalar, then kA = [k,a ij ]. This article covers the rule, all its properties (commutative, associative, distributive), how it differs from multiplying two matrices, and six worked examples.
Geometry
Shapes, proofs, and spatial thinking
Slope of Parallel Lines: Formula & Examples
The slope of parallel lines is the same for both lines: if two lines are parallel, then m₁ = m₂. This article explains why equal slopes force two lines to stay parallel, derives the rule, works through six examples, and clears up the mistakes that trip students up most.
Tetrahedron: Faces, Edges, Vertices, Volume, and Surface Area
A tetrahedron is a 3D solid with 4 triangular faces, 6 edges, and 4 vertices — the simplest possible polyhedron. A regular tetrahedron (all faces equilateral) has volume (√2)/12a³ and total surface area √3,a², where a is the edge length. This article covers its faces-edges-vertices count, derives the volume and surface-area formulas, shows its net, and works through examples.
Vectors in Math — Definition, Types, and Worked Examples
A vector is a quantity with both magnitude and direction, drawn as an arrow whose length is the size and whose arrowhead is the direction. This article covers the types of vectors, how to write them in component form, the core operations (addition, scalar multiples, dot and cross products), and the errors students hit most.
Trigonometry
Angles, waves, and circular harmony
Sin 47 Degrees — Value of sin(47°) and How to Find It
The value of sin 47 degrees is approximately 0.7314 — it is not a special-angle exact value, so there is no clean surd for it. This article shows how to find sin 47° honestly (calculator, the cofunction cos 43°, and table interpolation), gives the radian form, and places it on the unit circle.
Cot2x Formula : Proof, Graph, Properties, and Examples
The cot2x formula is cot 2x = (cot² x - 1)/(2cot x), the double-angle identity for cotangent. This article covers its proof from the cotangent angle-sum rule, three equivalent forms (in terms of tan x, in terms of sin and cos, and as 1/2(cot x - tan x)), the graph with its asymptotes, six worked examples, and the mistakes to avoid.
Law of Cosines : Formula, Proof, and Examples
The law of cosines states c² = a² + b² - 2abcos C, relating the three sides of any triangle to the cosine of one angle. This article covers when to use it (the SAS and SSS cases), its derivation, six worked examples, how it generalises the Pythagorean theorem, and the errors students make with obtuse angles.
Parenting
Raising confident, curious young mathematicians
Math Formulas
Every essential formula, explained and derived
Percentile Formula – Definition, Calculation, Examples
The percentile formula tells you where a value stands in a dataset: P = (number of values below x)/N × 100. This article covers both directions — finding the percentile of a value, and finding the value at a given percentile — with worked examples, the percentile-versus-percentage distinction, and the mistakes that trip students up.
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 r objects you can make from n distinct objects: ⁿP r = (n!)/((n-r)!). 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.
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: CP = SP - profit, CP = SP + loss, and from a percentage, CP = 100/(100 + profit%) × SP or 100/(100 - loss%) × SP. 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 = 1/2bh (or b/2√(a² - (b²)/4) from the equal side a and base b), perimeter = 2a + b, and height = √(a² - (b²)/4). 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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