Chapter 7 - Functions and Graphs - 7.2 Domain and Range - 7.2 Exercise Set - Page 459: 60

$a.\quad-3$ $b.\quad 9$ $c.\quad 23$

$ a.\quad$ $x= 0$ belongs to the interval $ x\leq 2$, so we calculate its function value with $f(x)=2x^{2}-3$ $f(00)=2(0)^{2}-3=-3$ $ b.\quad$ $x=3$ belongs to the interval $2\lt x \lt 4$, so we calculate its function value with $f(x)=x^{2}$ $f(3)=(3)^{2}=9$ $ c.\quad$ $x=6$ belongs to the interval $x\geq 4$, so we calculate its function value with$ f(x)=5x-7$ $f(6)=5(6)-7=30-7=23$