Equation 3 · Part 4 · How Scientific Instruments and Metrology Actually Work

Symbol x_2

y = f(x_1, x_2, \ldots, x_N)

x_2

What this part means

$x_2$ is an input to the expression that computes the quantity on the left.

Its job in the formula

$x_2$ is an input to the expression that computes the quantity on the left.

Full expressionSymbol x_2Article meaning

The passage around this formula

The GUM’s central move is to treat every measured or estimated quantity a result depends on as a random variable with its own estimated standard uncertainty, and then to propagate those uncertainties through the mathematical relationship that produces the final result. If a measurement result y is a function of N input quantities, y = f( $x_1$ , $x_2$ , $\ldots$ , $x_N$ ) , the combined standard uncertainty is obtained from a first-order Taylor expansion of that function:

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

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