Content deleted Content added
→top: "uniform scale" is not defined for Cartesian coordinates |
m →Properties: rm "diagonal" that usually means "slope = 1" + re "we" |
||
Line 13:
Such a function is called ''linear'' because its [[graph of a function|graph]], the set of all points <math>(x,f(x))</math> in the [[Cartesian plane]], is a [[line (geometry)|line]]. The coefficient ''a'' is called the ''slope'' of the function and of the line (see below).
If the slope is <math>a=0</math>, this is a ''constant function'' <math>f(x)=b</math> defining a horizontal line, which some authors exclude from the class of linear functions.<ref>{{harvnb|Swokowski|1983|loc=p. 34}}</ref> With this definition, the degree of a linear polynomial would be exactly one, and its graph
The natural [[Domain of a function|___domain]] of a linear function <math>f(x)</math>, the set of allowed input values for {{math|''x''}}, is the entire set of [[real number]]s, <math>x\in \mathbb R.</math> One can also consider such functions with {{math|''x''}} in an arbitrary [[field (mathematics)|field]], taking the coefficients {{math|''a, b''}} in that field.
| |||