Question

kimes
Let f(x)=\sqrt{7+x} and g(x)=\sqrt{7-x}.

(a) The domain of (f+g) is [

(b) The domain of (f-g) is

(c) The domain of (fg) is

(d) One of the following intervals is the domain of (f/g):
(1) [-7,7],
(2) [-7,7),
(3) (-7,7], or
(4) (-7,7).
Which one is the answer?
(Input 1, 2, 3, or 4)