PIC: Bradley Cooper Sports a Mustache

Would Renee have approved?

Bradley Cooper stepped out in Century City, Calif. on Wednesday with a new look: a thin mustache!

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Although Cooper, 36, has often sported a scruffy, unshaven look, it's the first time the Hangover 2 star has limited the facial fuzz to his upper lip.

Cooper has been laying relatively low since he and Renee Zellweger called it quits in mid-March after nearly two years together.

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 "She tried to make it work, but in the end it was too hard," source close to Zellweger (who celebrated her 42nd birthday solo in NYC last weekend) told Us . "Her friends feel bad it ended, but she's okay."

Cooper isn't exactly on the prowl for a new woman these days. "Bradley's absolutely obsessed with his career to the point that he cannot focus on anything else," says an insider.

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Tell Us: What do you think of Cooper's 'stache?