And: frequency/total = frequency
Mathematical frequency is equal to the number of times a certain data appears divided by the total number of this group of data. Frequency is usually expressed in proportion or percentage.
Under certain conditions, observing or testing the studied object is called a test every time the condition group is realized. The result is called an event. In experiments, events that may or may not occur are called random events.
Extended data
Nature:
1. When the number of repeated experiments n increases gradually, the frequency fn(A) shows stability and gradually stabilizes at a certain constant, which is the probability of event A. This "frequency stability" is also called statistical regularity.
2. Frequency has the following properties:
(1) Nonnegativity: 0 is less than or equal to fn(A) is less than or equal to 1.
(2) Normality: fn (ω) = 1 (Note: ω represents the sample space)
(3) additivity [1]
3. Frequency is not equal to probability. According to Bernoulli's theorem of large numbers, when n tends to infinity, the frequency fn(A) approaches the probability P(A) in a certain sense.
x? +y? ≤x+y
Let x=rcosθ and y=rsinθ.
And then r? ≤r(sinθ+cosθ)
r≤sinθ+cosθ
I=∫∫ xdxdy
=∫(-π/4