Expert guides for parents, students and math enthusiasts. Algebra to Olympiads — we've got you covered.
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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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Variables, equations, and the language of math
The solutions of a linear equation are the values that make the equation true when you put them back in. A one-variable equation like ax + b = 0 has exactly one solution; a two-variable equation like ax + by + c = 0 has infinitely many, and each one is an ordered pair (x, y) that sits on the equation's graph.
A singleton set (also called a unit set) is a set that holds exactly one element, written a, with cardinality 1. The single trickiest idea is that the element a and the set a are two different objects, which is why counts as a singleton even though its one element is the empty set.
Simultaneous linear equations are two (or more) linear equations that share the same unknowns and are solved together to find the values that satisfy all of them at once. You can solve them four ways: substitution, elimination, cross-multiplication, and graphing. A pair can have one solution, no solution, or infinitely many, and the coefficient ratios tell you which before you start.
Shapes, proofs, and spatial thinking
Constructing an angle of 60 degrees with only a compass and straightedge means building one corner of an equilateral triangle, whose three angles are each 60°. Draw a base ray, sweep an arc from the endpoint, sweep an equal arc from where it crosses, and join the vertex to the intersection. This article shows the step-by-step image series, proves why it lands at exactly 60°, and works through six examples.
An octahedron is a polyhedron with 8 faces, and the regular octahedron is a Platonic solid built from 8 equilateral triangles with 12 edges and 6 vertices. This article defines it, shows its properties, its volume and surface-area formulas, how it obeys Euler's formula F - E + V = 2, and worked examples.
A hexahedron is any polyhedron with six faces, and the most famous one is the cube, the regular hexahedron, with 6 square faces, 12 edges, and 8 vertices. This article covers the definition, the cube's volume a³ and surface area 6a², the other types of hexahedra, and Euler's formula.
Angles, waves, and circular harmony
The cosecant function is the reciprocal of sine, written csc x = 1/(sin x), so its graph is a series of U-shaped branches that never enter the band between -1 and 1. This article covers the definition, domain and range, the cosecant graph and its vertical asymptotes, period, key values, and six worked examples.
Sin A cos A equals 1/2sin 2A, the single-angle identity that rewrites the product of the sine and cosine of the same angle as half of its double-angle sine. This article covers the formula, its one-line derivation, the tangent form, six worked examples, the mistakes to avoid, and how it differs from 2sin Acos A and sin Acos B.
Sin3x equals 3sin x - 4sin³ x, the triple-angle identity that writes the sine of a tripled angle in terms of the sine of the single angle alone. This article covers the formula, its step-by-step derivation, the rearranged sin³ x form, six worked examples, the mistakes students make, and where the triple-angle identity is used.
Raising confident, curious young mathematicians
Every essential formula, explained and derived
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.
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.
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.
Crystal-clear definitions with worked 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.
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.
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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