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π Approximation Methods:

\[ \pi \approx 4 \times \left(1 - \frac{1}{3} + \frac{1}{5} - \frac{1}{7} + \frac{1}{9} - \cdots\right) \] (Leibniz series)

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1. What is π?

π (pi) is the ratio of a circle's circumference to its diameter, a fundamental mathematical constant approximately equal to 3.14159. It's an irrational number, meaning it cannot be expressed exactly as a simple fraction.

2. Approximation Methods

This calculator implements two common methods to approximate π:

Leibniz Series: \[ \pi \approx 4 \times \left(1 - \frac{1}{3} + \frac{1}{5} - \frac{1}{7} + \frac{1}{9} - \cdots\right) \]

Monte Carlo Method: Randomly generating points in a square and calculating the ratio that fall within an inscribed circle.

Note: The Leibniz series converges very slowly (about 300 terms for 2 decimal places), while Monte Carlo converges as 1/√N.

3. Importance of π

Details: π appears in many formulas across mathematics and physics. It's essential for calculations involving circles, spheres, periodic functions, and more.

4. Using the Calculator

Tips: Select a method and enter the number of iterations (for Leibniz) or random points (for Monte Carlo). Higher values give more accurate results but take longer to compute.

5. Frequently Asked Questions (FAQ)

Q1: Which method is more accurate?
A: Both methods converge to π, but Leibniz gives deterministic results while Monte Carlo is probabilistic. Leibniz is better for small numbers of iterations.

Q2: Why does Leibniz series work?
A: It's derived from the Taylor series expansion of arctan(1) = π/4.

Q3: What are other ways to calculate π?
A: Other methods include Archimedes' polygons, Machin-like formulas, Ramanujan series, and modern iterative algorithms.

Q4: How many digits of π are known?
A: As of 2023, π has been calculated to over 100 trillion digits, though most applications need only a few dozen.

Q5: Why is Monte Carlo called that?
A: The method uses randomness similar to games of chance in Monte Carlo casinos.

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