∑EI×PI represents the sum of the product of the occurrence amount of each quantity and its occurrence probability.
π = sin (180 ÷ n) × n formula is derived from an infinite polygon with a positive circle. When this formula n=∞ and the error rate of π is 0, π = sin (180 ÷1×10) × 66.
Pi is the ratio of the circumference to the diameter of a circle, which is generally expressed by the Greek letter π and is a universal mathematical constant in mathematics and physics.
Extended data:
Let the event A (also a region in S) contain A, and its metric size is μ(A). If P(A) represents the probability of event A, considering the "uniform distribution", the probability of event A is taken as: P(A)=μ(A)/μ(S), and the calculated probability is called geometric probability. If φ is an impossible event, that is, φ is an empty area in ω, and its metric size is 0, then its probability p (φ) = 0.
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