1. When the expression in the absolute value is greater than or equal to zero, directly remove the absolute value sign, and the result is the absolute value of the original expression.
For example: |5| = 5, |-4| = 4.
2. When the expression in the absolute value is less than zero, you need to add a negative sign in front of the result after removing the absolute value sign.
For example: |-5| =-(- 5) = 5.
In mathematics, absolute value is a basic concept. For any real number x, there are |x| = x(x≥0) or | x | =-x (x
(1) If the expression in the absolute value is greater than or equal to zero, the number itself can be obtained directly by removing the absolute value sign. This is because the absolute values of positive numbers and zeros are themselves.
(2) If the absolute value in the expression is less than zero, the result obtained after removing the absolute value sign is negative. This is because the absolute value of a negative number is its reciprocal.
Application of absolute value elimination method in senior high school mathematics
1, function .
In the function, we can transform the function into two functions by removing the absolute value, and then get the image of the original function according to the image of the function.
2. Number of shafts? .
On the number axis, we can transform the number axis into two number axes by removing the absolute value, and then get the representation of the original number axis according to the number axis.
3. plural? . In complex numbers, we can convert complex numbers into two complex numbers by removing absolute values, and then we can get the representation of the original complex number according to the representation of complex numbers.
4. Application questions? . In the application problem, we can use the method of removing absolute value to transform the application problem into two application problems, and then get the idea of the original application problem according to the idea of the application problem.