Ayew opened the scoring with an incredible volley in the first-leg of the Championship play-offs against Brentford.
The Ghana international’s amazing strike was enough as the Jack Army secured a narrow 1-0 win at home.
Ayew had earlier missed from the penalty spot in the 64th minute but picked himself up to score a goal of the season contender.
Cooper was impressed with the attacker’s positive mentality after missing from the spot and praised the player for being able to brush off the setback.
“Andre has missed a penalty, but brushed it off and raised his game even more, and it came off with the goal. To have such an impact and score the goal tells you everything about the mentality he has,” the Swansea City boss said.
“His mentality is of the highest order, to brush off the disappointing return from a penalty where you fancied him."
He added: “To have such an impact and score the goal tells you everything about the mentality he has. If anything, the miss affected him in a positive way.
“He is really important for us, and what is more impressive with his goalscoring record is that for a lot of the season he has played out wide, and not through the middle.”
Ayew has now scored 18 goals in all competition this season, 16 of which have come in the Championship.
The Ghanaian will be hoping to help the Jack Army secure qualification to the Premier League next season.