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 objective function is the linear expression a linear programming problem sets out to maximize or minimize — usually written , where and are decision variables. This article defines it, shows the form, works six examples, and separates it clearly from the constraints.
The scalar triple product of three vectors is , a single number equal to the signed volume of the parallelepiped built on those vectors. This article covers the definition, the determinant formula, six worked examples, why a zero result means the vectors are coplanar, and the mistakes to avoid
The square root 1 to 25 chart gives through , where five values () are exact whole numbers and the other twenty are irrational, rounded here to three decimals. This article gives the full table, marks rational versus irrational, and shows how to read and rebuild it.
Shapes, proofs, and spatial thinking
The vertex of a parabola is its turning point - the highest or lowest point on the curve - found from using , then . This article covers the vertex formula, how to find it from standard, vertex, and intercept forms, six worked examples, and the sign mistake that flips the answer.
Vector subtraction finds the difference of two vectors by adding the negative of the second: . This article covers the component formula, the triangle and parallelogram methods, why subtraction is not commutative, the tip-to-tip direction of the result, and worked examples that turn the rule into a picture.
The vectors triangle inequality states that for any two vectors, - the length of a sum never exceeds the sum of the lengths. This article states the full two-sided form, proves it two ways, pins down exactly when equality holds, and works six examples.
Angles, waves, and circular harmony
The derivative of is . The extra factor of comes from the chain rule, because is an inner function whose own derivative is . This article covers the formula, the chain-rule proof, a first-principle derivation, the anti-derivative, worked examples, and the mistakes students make most.
Csc, sec, and cot are the three reciprocal trigonometric functions: , , and . This article defines all three, gives their domains, ranges, periods, and graphs, connects them through the Pythagorean identities, and works six examples. For the single-function deep dive, the cosecant page goes further on csc alone.
The value of cot pi/6 is exactly , because and at that ratio is . This article shows the 30-60-90 triangle proof, the unit circle, a standard-angle table, five worked examples, and the mistake that swaps it with tangent.
Raising confident, curious young mathematicians
Every essential formula, explained and derived
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 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.
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.
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: , , 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.
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.
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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