Question

b) Given

p="Front door is open

q="Back door is open"

r="Light is on"

s="The lift doors are open"

t="The lift is moving",

i)

write the following sentence in logic symbols: "When the front and back

doors are closed then the light is off"

write the following in words: SV (t As)

ii)

Answer 1

1)$(\lnot p \land \lnot q) \to \lnot r$

2)Assuming SV (t As) being following formula $s \lor (t \land \lnot s)$ this should be written in words as "The lift doors are open or lift doors are closed and lift is moving."