Quality Content Incentive Program Promoted to junior high school, to the seventh grade, the first difficult problem you come into contact with should be the absolute value, for the absolute value to understand from two aspects, one is its algebraic meaning, the other is its geometric meaning, relatively speaking, understand its geometric meaning, the algebraic meaning is easy to understand. The geometric meaning of an absolute value refers to the distance of a point on the number line from the origin. Look, it's a distance, it's a distance, it can't be negative, so its algebraic meaning is that the absolute value of any number can't be negative, according to the law, it is divided into three situations to go to the absolute value symbol.
The above figure is an absolute value operation problem that uses the number axis to simplify, there are three knowledge points here, one is the number represented by any point on the number line, the number on the right is always greater than the number on the left;The second is the operation method of removing the absolute value sign, that is, the absolute value of a positive number is equal to itself, the absolute value of a negative number is equal to its opposite number, and the absolute value of 0 is equal to 0;The third is that the absolute value of the difference between the two numbers is equal to the large decrease, and the absolute value of the sum of the two numbers should first judge its positive and negative, and then apply the law.
How?Is it the same as the result of your calculations?
The link to the column released by the teacher is the full solution of the seventh grade mathematics in the first volume, which is sent by the big coffee teacher Xiaohong's thinking, and it is about to be the end of the term, so as to quickly take pictures of the Xi and learn the Xi, so that there will be a leap in the end of the term!