Now, for Math Nerds!

[Paradox]

Same prizes as this thread

f(x) = 3x + 1 - 3 (5+3)

What are the range values (I will decode this later on in the post if nobody gets it) when the domain is
D = {-1, 2, 5}

f(x) = 3x+1-3(5+3)


f(x) = 3(-1)+1-3(5+3)
f(x) = (-3)+1-3(8)
f(x) = (-3)+1-24
f(x) = (-2)-24
f(x) = (-26)


f(x) = 3(2)+1-3(5+3)
f(x) = 6+1-3(8)
f(x) = 6+1-24
f(x) = 7-24
f(x) = (-17)


f(x) = 3(5)+1-3(5+3)
f(x) = 15+1-3(8)
f(x) = 15+1-24
f(x) = 16-24
f(x) = (-8)


r={-26,-17,-8}