Equation 3 · Part 4 · Comparing the Main Approaches to Scientific Instruments and Metrology

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

…without an accompanying uncertainty, the number cannot be compared against another laboratory’s figure, however precise the instrument sounds. The combined standard uncertainty $u_c(y)$ for a measured quantity y = f( $x_1$ , $x_2$ , $\ldots$ , $x_N$ ) that is a function of several independently uncertain inputs is, to first order,

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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 surrounding passage

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