Question

let f (t) be the outside temperature t hours after 9 am
a. f(4)=75
B: f(m)=70
C: f(2)=f(9)
D: f(6) > f(0)

Answer 1

A statement (in logic) is a declarative sentence that is either true or false.

- a. f(4) = 75 — statement (specific time t = 4, so it's either true or false).
- b. f(m) = 70 — not a statement as written (m is an unspecified variable, so this is an open sentence).
- c. f(2) = f(9) — statement (both sides refer to specific times, so it's either true or false).
- d. f(6) > f(0) — statement (specific times, so either true or false).

So a, c, and d are statements; b is not.