26. Draw the graph of a;^ — 4 a; + 2 from a; = — 1 to a; = 4,
and from the diagram determine :

(a) The values of the function if a; = - 1 1^, 2f



(&) The values of a;, if a;2 _ 4 j, _|_ 2 equals — 2, 1, 1|-.
(c) The smallest value of the function.
(d) The value of x that produces the smallest value of the
function :

(e) The values of x that make a;2 — 4 a; + 2 = 0.
(/) The roots of the equation a? — 4,x + 2 = Q.
(g) The roots of the equation x' — '^x + 2 = —l.
Qi) The roots of the equation a;2 — 4 a; + 2 = 2.
* If necessary, use for the ordinates a smaller unit than for the ab-



FUNCTION OF ONE VARIABLE 11

27. Draw the grapli oiy = 2 + 2x — x', from » = — 2 to a; = 4,
and from the diagram determine :

(a) The values of y, i.e. the function, if x =^, — 1 J, 2J.
(6) The values of a; if y = — 2.
(c) The greatest value of the function.
(d) The value of x that produces the greatest value of y.
(e) The values of x if the function equals zero.
(/) The roots of the equation 2 + 2x — a?=0.
(g) The values of x it y = l.
(li) The roots of the equation 2 + 2x — a? = l.
