Brevet maths revision sheets: Pythagoras, Thales, trigonometry, linear functions, probability and Scratch. Key formulas, theorems and worked examples.
The French Brevet maths exam lasts 2 hours and is scored out of 100 points. It covers the entire cycle 4 curriculum (Years 9-11 in the French system), with emphasis on the final year. The exam contains five to seven independent exercises spanning four domains: numbers and calculations, geometry, functions, and statistics-probability. An algorithmic exercise using Scratch is always included.
Master all four operations with fractions:
Key rules: a^n × a^m = a^(n+m), a^n / a^m = a^(n−m), (a^n)^m = a^(n×m), a^0 = 1, a^(−n) = 1/a^n.
Scientific notation: write numbers as a × 10^n where 1 ≤ a < 10. Example: 0.00045 = 4.5 × 10^(−4).
Properties: √(a × b) = √a × √b, (√a)² = a, √(a²) = |a|.
Simplification: extract perfect squares. Example: √72 = √(36 × 2) = 6√2.
Warning: √(a + b) ≠ √a + √b.
Three essential identities (must know by heart):
In a right triangle with hypotenuse BC: BC² = AB² + AC².
Use the direct theorem to calculate a missing side, the converse to prove a triangle is right-angled, and the contrapositive to prove it is not.
When two parallel lines are cut by two secants meeting at point A: AB/AD = AC/AE = BC/DE.
Use it to calculate lengths (direct theorem) or prove lines are parallel (converse).
In a right triangle, for an acute angle α:
Mnemonic: SOH-CAH-TOA. Use trigonometry to find a missing side (when you know an angle and a side) or a missing angle (when you know two sides).
Key transformations: reflection (axial symmetry), point symmetry (central symmetry), translation (shifts by a vector), rotation (turns around a center by a given angle), and enlargement/reduction (homothety with ratio k, where areas scale by k² and volumes by k³).
Essential volume formulas:
To find the equation from two points A(x₁, y₁) and B(x₂, y₂): calculate slope a = (y₂ − y₁)/(x₂ − x₁), then solve for b.
Every Brevet exam includes a Scratch exercise. Know the key structures: variables, loops (repeat n times, repeat until), and conditionals (if...then...else). Common tasks include drawing regular polygons (repeat n times: move c steps, turn 360/n degrees) and computing sums or sequences.