Answer:
[tex]f^-1 (x) = -3-x[/tex]
Step-by-step explanation:
[tex]f(x) = -x-3\\f(x) = y\\y = -x-3[/tex]
Now we have to change the "x" into "y" and viceversa
[tex]x = -y-3\\[/tex]
Then,
[tex]x+3=-y\\x+y = -3\\y = -3 - x\\f^-1 (x) = -3-x[/tex]
