Answer:
Logic with the use of Truth Table
Step-by-step explanation: a) Oleg is a math major= P; Oleg is a economic major=Q; Oleg is required to take math 362=R; Oleg is not required to take 362=←R
b)i) Oleg is a math major or Oleg is an economic major:
P║ Q ║ P∨Q
T T T
T F T
F T T
F F F
ii) Oleg is a math major, then Oleg is required to take Math 362:
P║ R ║ P∧ R
T T T
T F F
F T F
F F F
iii) Oleg is an economic major or Oleg is not required to take Math 362:
Q║ ←R ║ Q ∨ ←R
T T T
T F T
F T T
F F F
c) It is valid because Oleg can only take Math 362 since Oleg is a math major, therefore, it follows that, R ∧ ( P ∨ Q) is valid.