Prove that
`~(pvvq)cong~pwedge~q`

Prove that ~(~pto ~q) -=~p ^^q

Prove that : ~(prArrq)=p^^(~q)

Using truth table, prove that : ~[(~p) wedge q] is logically equivalent to p vee (~q) .

Prove that q^^~p -=~ (q to p)

prove that (p^^q) ^^~(pvvq) is a contradiction.

Prove that ~((~p)^^q) -=pvv(~q) .

In the adjoining figure, angleBAC=angleBDC and angleABC=angleBCD . Prove that : (i) DeltaABC cong DeltaDCB (ii) DeltaABE cong DeltaDCF .

In a tringle ABC, AB = AC and bisector of angle A meets BC at D. Prove that : (i) DeltaABD cong DeltaACD (ii) AD is perpendicular to BC.

The following figure shows a square ABCD and an equilateral triangle DCE. Prove that : (i) angleADE=angleBCE=150^(@) (ii) DeltaADE cong DeltaBCE (iii) AE = BE

The adjoining figure shows a square ABCD and an equilateral triangle DEC. Prove that : (i) angleADE=angleBCE=30^(@) (ii) DeltaADE cong DeltaBCE