Question

Find f o g and g o f, if they exist. State the domain and range

f={(-4,-14),(0,-6),(-6,-18),(2,-2)}
g={(-6,1),(-18.13),(-14,9),(-2,-3)}

Answer 1

(f o g)(x) = f(g(x))

g(-6) = 1
f(-1) does not exist

(fog)(-18) nope
(fog)(-14) nope
(fog)(-2) nope

For no value does fog exist

(gof)(-4) = 9
(gof)(0) = 1
(gof)(-6) = 13
(gof)(2) = -3
So, the domain of gof is the domain of f.