I believe he apologizes because he is ultimately responsible for the death of Ophelia and his father Polonius. Also, Hamlet finally sees how similar they are to each other and offers his apology to prevent him from following the same destructive path Hamlet did.
Why not? If it be not now, yet it will come. The readiness is all. Hamlet's rescue from Claudius's trap by the pirates has made him fatalistic. He decides that if this is how he is going to get within range of Claudius with a weapon in his hand then so be it. He has stopped wanting to perfect his revenge so it will send Claudius to the deepest part of Hell. Killing him will be enough now.
By this stage in the play, Hamlet has developed a philosophy of "going with the flow". He has given up on trying to control events, so he will go along with what is happening and take his chance when he may. "If it be not to come, it will be now, if it be not now, yet it will come. The readiness is all."
The Laertes in Hamlet doesn't do this. Are you thinking of some other Laertes?
Polonius, Ophelia, Gertrude, Hamlet, Claudius, and Laertes.
Technically, King Cladius Kills Gertrude in Hamlet, but not intentionally. King Cladius poisons the wine for Hamlet to drink but he refuses it to keep fencing Laertes but when hamlet makes the second strike the Queen wants to drink to him and when she does she drinks from the poisoned cup and dies.
Poisoned sword
does* and it's a duel that was set up before by Laertes and Claudius to kill Hamlet. For Laertes because Claudius told him that Hamelt murdered his brother and for Claudius so Hamlet doesn't spill the secret that Claudius murdered Senior Hamlet.
Laertes - Hamlet - was created in 1600.
Laertes annoints his sword in order to poison Hamlet, however at somepoint in the match (after Laertes poisons Hamlet, but before Hamlet is killed by the poison), Laertes and Hamlet switch swords and Hamlet also poisons Laertes.
Laertes is killed by the poisoned sword that he originally killed Hamlet with. After wounding Hamlet with the poisoned sword, the swords are switched and Hamlet wounds Laertes with the poisoned sword.
First, Laertes stabs Hamlet with it. Then Hamlet takes it from Laertes and stabs Laertes with it. Then Hamlet stabs Claudius with it before forcing the poisoned wine down Claudius' throat.
Hamlet thought a lot about avenging his father's murder, but Laertes acted on his desire to avenge his father's murder.
In Ophelia's grave.
Laertes is the son of Polonius and brother to Ophelia whom Hamlet loves. King Claudius poisons Laertes's sword with the intent to kill Hamlet in the tragedy play by Shakespeare titled Hamlet.
The Laertes in Hamlet doesn't do this. Are you thinking of some other Laertes?
Laertes is the son of Polonius and the brother of Ophelia.
Hamlet and Laertes become brothers when Hamlets mom get's married to Laertes's father Cladious.
Because he and King Claudius planned it...they put poison on the end of the sword so that when Laertes stabs Hamlet, Hamlet dies. The motive also has to do with the fact that Laertes is avenging his father's (Polonius's) death, whom was killed by Hamlet.
1. Laertes' sword is unbaited 2. Laertes' sword is poisoned 3. Hamlet's drink is poisoned