Bendtner, starting in the league for the first time this season in place of Olivier Giroud, headed in Carl Jenkinson's right-wing cross after just two minutes to put the Gunners in front.
It looked like a prelude for convincing home win but the Tigers kept things tight for much of the remainder of the first half.
That all changed within two minutes of the restart when Mesut Ozil ran onto Aaron Ramsey's neat reverse pass to slide the ball in from eight yards.
The visitors threatened rarely as the Gunners cruised through the remainder of the match to retain their top of the table advantage.
After their blistering start, Arsenal - who had made several changes from the team which won at Cardiff, including starting with England trio Jack Wilshere, Theo Walcott and Kieran Gibbs on the bench - continued to push Hull back.
Santi Cazorla's goal-bound shot was blocked and Allan McGregor then spilled a low effort from Ozil which Bendtner could not turn in.
The Tigers slowly found some momentum and a centre from Robbie Brady flew across the face of the Arsenal goal.
When the Gunners did press the visitors back, they were guilty of some poor finishing, with the usually accurate Ramsey smashing an 18-yard effort high into the Clock End.
The Welshman's radar was, though, locked on target in the 31st minute, this time a low 20-yard effort that was set for the bottom-right corner being pushed away by the Hull keeper at full stretch.
City defender Maynor Figueroa upended Cazorla in front of the technical area, but referee Andre Marriner deemed the hefty sliding challenge fair.
Bendtner turned provider just before the break when he was played in on the overlap down the right and clipped the ball back through the six-yard box where Ozil just could not guide his header goalwards.
The German playmaker was on the scoresheet soon after the restart. Nacho Monreal kept the ball in on the left touchline, and gave it to Ozil. His sliderule pass found Ramsey on the edge of the box, before the Wales international turned away from goal and then played an exquisite reverse ball back into the path of Ozil, who coolly tucked it into the net from 10 yards and Arsenal led 2-0 in the 47th minute.
Brady was then perfectly placed on the post to flick away a backward header from Bendtner which may have been dropping into the far corner.
Hull made a double change on 58 minutes. Forward Danny Graham was replaced by George Boyd and Brady came off for Liam Rosenior.
Hull striker Yannick Sagbo collided with Arsenal keeper Wojciech Szczesny as they challenged for a ball through the six-yard box, but after the Pole had some brief treatment on his head, play resumed.
Arsenal, who have now started to show really depth with the return of their injured players, sent Walcott and Wilshere on for the last 17 minutes, replacing Bendtner and Tomas Rosicky.
As the clock ran down, Tigers boss Steve Bruce was involved in a few exchanges with the jubilant Arsenal fans behind the visitors' bench - most of which were taken in good spirits by the former Manchester United defender.
Afterwards, Arsene Wenger sang the praises of Bendtner saying: "It was a good performance from Nicklas. He has come back and worked hard on training. I know he has the qualities to play for us and he showed that tonight.
"When he has that type of attitude and commitment it shows that he has the qualities. Much depends on his commitment and fitness. He has worked hard recently but when he is physically sharp he can compete with anybody."