Which constant (≈ 3.14159) is the ratio of a circle's circumference to its diameter?
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Pi
Its decimals never end.
💡 Did you know? March 14 (3.14) is “Pi Day”.
All questions with answers
Which constant (≈ 2.718) is the base of the natural logarithm?
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Euler's number
It describes natural growth and decay.
💡 Did you know? Like pi it is irrational and transcendental.
Which proportion (≈ 1.618) is seen as especially harmonious, the “divine proportion”?
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Golden ratio
It appears in art, architecture and nature.
💡 Did you know? It is closely tied to the Fibonacci sequence.
Which irrational number (≈ 1.414) multiplied by itself equals exactly 2?
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Square root of 2
It is the diagonal of the unit square.
💡 Did you know? Its irrationality shocked the ancient Greeks.
What is the number i, whose square is −1, called?
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Imaginary unit
It enables complex numbers.
💡 Did you know? No real number can do this.
Which symbol (∞) stands for a quantity without end?
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Infinity
The symbol is called a “lazy eight”.
💡 Did you know? There are even different sizes of infinity.
What is the number 10 to the power 100 (a 1 with a hundred zeros) called?
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Googol
It exceeds the number of atoms in the universe.
💡 Did you know? The search engine Google is named after it.
What is 10 to the power of (10 to the power of 100) called?
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Googolplex
It could never be fully written down.
💡 Did you know? It is unimaginably larger than a googol.
What is the circle constant τ, equal to twice pi (≈ 6.283), called?
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Tau
It is the ratio of circumference to radius.
💡 Did you know? Some find it more “natural” than pi.
What is γ (≈ 0.577), linking the logarithm and the harmonic series, called?
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Euler-Mascheroni constant
Whether it is rational is still unknown.
💡 Did you know? It is one of maths' great open questions.
Which number is the neutral element of addition?
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Zero
Adding zero changes nothing.
💡 Did you know? Inventing it as a number was a big step.
Which number is the neutral element of multiplication?
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One
Multiplying by one changes nothing.
💡 Did you know? It is not considered a prime.
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