All students need to have good study habits(习惯). When you have good study habits, you can learn things quickly. You also remember them easily. Do you like to study in the living-room? This is not a good place because it is usuallytoo noisy. You need to study in a quiet place, like your bedroom. A quiet place will help you only think about one thing, and you will learn better. Before you begin to study, do not forget to clean your desk. A good desk light is important, too. You are feeling tired easily if there is not enough(足够的) light.

在平面直角坐标系中，抛物线y=x²﹣6mx+5与y轴的交点为A，与x轴的正半轴分别交于点B（b，0），C（c，0）．