Question

Find the negation of each: 1.

∃

x ( (x+3=2) ^ (x

-

2 =1))

Answer 1

$\nexists x ( (x+3=2) \land (x-2 =1)) = \forall x (\lnot(x+3=2) \lor \lnot (x-2 =1)) = \forall x ((x+3\ne2) \lor (x-2 \ne 1)) = \forall x (x\ne -1\lor x\ne 3)$