Let p denote 'price' increases' and q denote 'demand falls'. Express the following in the symbolic form :
(1) Price increases, then demand falls.
(2) If price does not increase, then demand does not fall.
(3) Price increases if and only if the demand falls.

Answer

(1) `ptoq` (2) `~pto~q`
(3) `p""iffq`