England restricted their opponents to 222 all-out, with Steve Finn and Stuart Broad both taking three wickets each in an impressive attacking display.
Cook, meanwhile, continued to impress with the bat – the England skipper was eventually dismissed for 80 runs before Kevin Pietersen and Eoin Morgan helped eclipse Pakistan’s total, sealing the victory with 12 overs to spare.
“Our bowlers were outstanding, we may have been slow to start with but to keep them to 220 on that wicket was a fantastic effort,” Cook told Sky Sports.
“I thought everybody contributed with the ball, 220 was quite a long way below par.
“We’ll obviously enjoy it tonight, winning the series, but we’ve come here to win every game in the series and hopefully we can come back here in three days’ time and put in a really good performance again.
Pietersen was the pick of England’s batsmen as the 31-year-old hit an unbeaten 111 from 98 balls – his first one-day century since 2008.
And he admitted it was a relief to finally perform with the bat after a frustrating series.
“It was nice to get some runs, I said yesterday that I’m not at a stage where I don’t know where my next run is coming from, I’m just getting out in silly little ways,” he said.
“I’m always getting starts and then getting myself out, so with a little bit of fortune I was lucky enough to get to three figures today.”
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