题目

Interviewer: Tracy Lester is with us in the studio.Welcome Tracy! We are all interested to know about your life as a child actor.You’re only fourteen years old— yet you are already famous! Tracy: Yes. I'm really lucky to have a chance to do so many things that other young people haven't yet. Interviewer:So Tracy, the first question is—how old were you when you made your first movie, peanuts?Tracy: Well, I was only four—so I didn't have a big part—and that movie wasn't really successful.Interviewer: So what was your first successful movie then?Tracy: Chocolate Aliens. Did you see it? 关于x的一元二次方程，问：是否存在整数k使方程有两个不相等的实数根，若存在，请求出k的值并求出此时方程的两个实数根；若不存在，试说明理由．