What is the theorem a² + b² = c² for right triangles called?
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Pythagorean theorem
c is the longest side, the hypotenuse.
💡 Did you know? It holds only in right triangles.
All questions with answers
What does the formula π · r² compute?
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Area of a circle
r is the radius of the circle.
💡 Did you know? π is about 3.14159.
What does the formula 2 · π · r compute?
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Circumference
It is the length of the circle's edge.
💡 Did you know? Using the diameter: π · d.
What does the formula length × width compute?
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Area of a rectangle
For a square it is a × a = a².
💡 Did you know? Area is measured in square units.
What does the formula (base × height) ÷ 2 compute?
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Area of a triangle
The height is perpendicular to the base.
💡 Did you know? A triangle is half a rectangle.
What does the formula a³ (edge length cubed) compute?
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Volume of a cube
All edges of a cube are equal.
💡 Did you know? Volume is measured in cubic units.
What does the formula (4/3) · π · r³ compute?
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Volume of a sphere
Archimedes found this in antiquity.
💡 Did you know? A sphere has the least surface for a given volume.
What is the identity (a + b)² = a² + 2ab + b² called?
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Binomial formula
There are three binomial formulas.
💡 Did you know? They speed up expanding brackets.
What do you compute with distance divided by time?
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Speed
v = s / t.
💡 Did you know? Measured in km/h or m/s.
What does the formula mass × acceleration (F = m · a) compute?
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Force
It is Newton's second law.
💡 Did you know? The unit of force is the newton.
What does base amount × rate ÷ 100 compute?
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Percentage value
20% of 50 is 10.
💡 Did you know? The base value is 100%.
What is the solution formula x = (−b ± √(b² − 4ac)) ÷ (2a) called?
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Quadratic formula
It solves ax² + bx + c = 0.
💡 Did you know? The term under the root is the discriminant.
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