MATHEMATICS · Multi-part · AP · AP Precalculus · Polynomial and Rational Functions · Polynomial and Rational Functions
Problem
Let f(x)=x2.
(i) Choose any five non-zero values of x and tabulate the corresponding y-values. Show that for every chosen x, the same y occurs at −x.
(ii) Hence, prove that f(x) is an even function.
(iii) Using this property, justify why it is sufficient to plot the graph only for x≥0 and then reflect it to obtain the complete graph.
(iv) After drawing the full graph, estimate the set of all real numbers x for which y<3 and express your answer in interval notation.