Step-by-step explanation:
[tex]f( \frac{2}{3} x) = \frac{4}{9} {x}^{2} - 1 \\ \frac{4}{9} {x}^{2} - 1 = 0 \\ \sqrt{ {x}^{2} } = \sqrt{ \frac{9}{4} } \\ x = \frac{3}{2} \\ x = - \frac{3}{2} [/tex]
we have three points of the graph
(0,-1) min point
and those two values for x.
so:
