suatu fungsi f(x)= -2x – 1 dengan domain {x|x<12,xE bilangan ganjil} tentukan daerah asli dan angotanya

Domain = {1,3,5,7,9,11}

f(x) = -2x-1
maka,
f(1) = -2.1-1 = -2-1 = -3
f(3) = -2.3-1 = -6-1 = -7
f(5) = -2.5-1 = -10-1 = -11
f(7) = -2.7-1 = -14-1 = -15
f(9) = -2.9-1 = -18-1 = -19
f(11) = -2.11-1 = -22-1 = -23
maka,
daerah hasil : {-3,-7,-11,-15,-19,-23}