Thus the relation in Figure 7 (page 76) is not a function since for a given value of V, x + y agt; 6 has many solutions. ... In Figure 10, a vertical line, two units to the right of the origin, intersects the graph of y2 = x twice. ... CARTESIAN PRODUCTS When we graph a set of pairs (x, y) that satisfy a sentence such as y = x2, we are selecting a subset of all the points of the plane to picture the relation. ... We call it the Cartesian product (after Reneaquot; Descartes) of L and L and symbolize it by a#39;L X La#39;.
|Title||:||The growth of mathematical ideas, grades K-12|
|Author||:||National Council of Teachers of Mathematics|