A function assigns one output to each permitted input. A table lists selected input–output pairs; the graph shows their relationship. Choose clear scales, calculate carefully and plot each pair. Use a smooth curve for a smooth function, not straight joins between successive points. Example For y=x3-x+1 on -2 <= x 2, the expression is a sum of three power terms. Its values are: **x** | **y** -2 | -5 -1 | 1 0 | 1 1 | 1 2 | 7 The equal outputs at -1,0,1 do not make the curve horizontal between them. Additional values, such as y=1.375 at x=-0.5 and y=0.625 at x=0.5, reveal the shape. Do not extend a graph beyond its stated interval.

A function assigns one output to each permitted input. A table lists selected input–output pairs; the graph shows their relationship. Choose clear scales, calculate carefully and plot each pair. Use a smooth curve for a smooth function, not straight joins between successive points.

For \(y=x^3-x+1\) on \(-2\le x\le2\), the expression is a sum of three power terms. Its values are:

The equal outputs at \(-1,0,1\) do not make the curve horizontal between them. Additional values, such as \(y=1.375\) at \(x=-0.5\) and \(y=0.625\) at \(x=0.5\), reveal the shape. Do not extend a graph beyond its stated interval.

\(x\)	\(y\)
\(-2\)	\(-5\)
\(-1\)	\(1\)
\(0\)	\(1\)
\(1\)	\(1\)
\(2\)	\(7\)

Tables, curves and the permitted interval

Tables, curves and the permitted interval