The addition of a sequence of numbers can be represented with the summation symbol (Σ).
Consider an addition sequence, Sn. Suppose the numbers to be added are u1, u2, u3, …, un. We let
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The sigma (Σ) symbol represents a summation of n components. As n increases without bound…
…we are led to consider a summation over infinite components, which is denoted by
Such an expression is called an infinite series. As an example, we can write the equation of state for a mixture of gases:
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where P = total pressure |
Pi = partial pressures of all i gas species | |
ni = particle number per unit volume | |
k = Boltzmann’s constant, and | |
T = temperature |
This equation describes the total pressure P, as the summation of partial pressures Pi.
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