LOS ANGELES, May 31: Pop singer Mariah Carey and rapper Nicki Minaj will leave “American Idol” after just one season as judges on the singing contest show, following on the heels of longtime judge Randy Jackson who left amid a TV ratings slump. “Thank you American Idol for a life changing experience! Wouldn’t trade it for the world! Time to focus on the Music!!!” Minaj said on her Twitter page on Wednesday. (agencies)