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mohamed el teir
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when saying the probability distribution of X is f(x) = (3 x) this is to be like vector notation where 3 is above x but i can't write it like this here. what is meant by this notation ?
Yes. It's the number of combinations of 3 things taken x at a time. It's usually read as "3 choose x."ProfuselyQuarky said:That's a combination, right? I haven't done those since last summer.
What is the definition of f(x)? The combination term is a coefficient of the probability term for exactly x.FactChecker said:One problem with that interpretation of the notation is that the distribution function will not total 1. Is it possible that the definition of f(x) is missing a multiplier?
The original post stated: "the probability distribution of X is f(x) = (3 x) ". If we interpret that as f(x) = 3Cx, then it does not total 1.mathman said:What is the definition of f(x)? The combination term is a coefficient of the probability term for exactly x.
Good catch. That has to be it.HallsofIvy said:I suspect that the OP is completely misreading what is said and that it really is something that involves [itex]\begin{pmatrix}3 \\ x \end{pmatrix}[/itex] such as the binomial distribution with n= 3, [itex]f(x)= \begin{pmatrix}3 \\ x \end{pmatrix} p^x (1- p)^{3- x}[/itex] for x= 0, 1, 2, or 3.
This is a common question asked by students who are new to scientific notation. In short, scientific notation is a way of writing numbers that are very large or very small. It is written in the form of a number between 1 and 10 multiplied by a power of 10. For example, 3.5 x 10^4 is the scientific notation for 35,000.
Scientists use scientific notation to make large or small numbers easier to work with. It is also useful when working with very precise measurements, such as in chemistry or physics. Additionally, scientific notation allows for easier comparison of numbers with different orders of magnitude.
To convert a number into scientific notation, you need to move the decimal point to the right or left until there is only one non-zero digit to the left of the decimal point. The number of times you move the decimal point determines the power of 10. For example, 2,500 in scientific notation is 2.5 x 10^3.
Standard notation is the typical way of writing numbers, with a single digit to the left of the decimal point and any remaining digits to the right of the decimal point. Scientific notation, on the other hand, uses a number between 1 and 10 multiplied by a power of 10. Standard notation is used for everyday numbers, while scientific notation is used for very large or very small numbers.
Of course! A common example of a number written in scientific notation is the speed of light, which is approximately 3 x 10^8 meters per second. Another example is the mass of an electron, which is approximately 9.11 x 10^-31 kilograms.