题目

已知函数y=f（x）的图象在点M（1，f（1））处的切线方程是y=x+3，则：f（1）+f′（1）=． 答案：4 ． 【考点】导数的几何意义． 【专题】导数的概念及应用． 【分析】根据题意吧，求出切点坐标，得出f（1）的值，根据导数的几何意义判断f′（1）求解． 【解答】解：∵函数y=f（x）的图象在点M（1，f（1））处的切线方程是y=x+3， ∴f（1）==，f′（1）=， ∴f（1）+f′（1）==4 故答案为：4 【点评My grandpa is 93 years old this year. He is very healthy and looks young. Many people ask him why he is so healthy.Grandpa says good diet is very important to everyone. Grandpa has three meals a day regularly(有规律地). He often eats lots of vegetables and fruit. He never drinks or smokes(抽烟). He says they are bad for health. After he gets up in the morning, he often drinks a cup of water. And before he goes to bed in the evening, he has a cup of milk. He says everyone should drink some water before breakfast.Grandpa has a good lifestyle, too. He likes sports. He likes playing ping-pong and badminton. Sometimes he goes swimming. He goes running every day before breakfast, too. He says exercise can help a person keep healthy and strong. Grandpa likes watching TV. But he only watches TV in the afternoon. He doesn’t watch too much TV. Many old people like playing Majon, but grandpa doesn’t. He says sitting in the chair for long time is not good for health.1.What makes grandpa so healthy？A. Only a good dietB. Eating three meals regularly.C. A good diet and lifestyle.D. Sports activities.2.Grandpa usually __________ before he goes to bed.A. drinks some water B. drinks some milkC. drinks some tea D. drinks some juice3.How often does grandpa go running?A. Every day. B. Twice a weekC. Every week D. Sometimes4.Grandpa thinks playing Majon is_________ for health.A. good B. important C. bad D. helpful5.What’s the main idea of the passage?A. Grandpa’s Diet B. I Want to Be HealthyC. How Can We Look Young D. Why Is Grandpa Healthy