There's no need for Arteta to encourage they boy's to put the same energy they are putting in champions League to premier league because they can't lift the premier league title is already too late the league is already about to end and Liverpool are still very much inform so that opportunity for them to carry the premier league title is not there anymore and again the point gap is too much so is better they focus in the champions League and not focus on both because if they put there focus in both they will surely be distracted however I really don't see any possibility of arsenal lifting the champions League title this season but anything can happen just like the way people never believed arsenal will win real Madrid but Barcelona is the club I feel will win this seasons champions League because they are so inform and strong.
Arsenal has lost lifting the premier league title two seasons now because of lack of consistency they need to be consistent always and also get a good striker if they really want to lift the premier league title and stop coming second always.
You are right, but Nottingham isn't "too" far off, yeah it's still a bit off, but they are close enough in case Arsenal loses one more game. This is the reason why Arsenal is trying to win every game they can, not for the title, if they try to win the title they can't, but the path is the same, just like how you would need to win every game to make sure you win the title, they need to win every game so they do not go back down to third place.
This will not help them get the title, but keep second position. UCL is doing great for them too, they managed to beat Real Madrid easily, so they should not be really worried about it. They will most likely beat Real Madrid, even if they lose next game, they won't lose with 3 goal difference I assume, and they will finish the league second too.