Defining a Mathematical Inequality
An inequality is a mathematical statement that compares two values or expressions that are not equal. Instead of using an equal sign (=), it uses a relational symbol to show that one value is greater than, less than, or not equal to another, indicating a range of possible values rather than a single solution.
Section 2: The Symbols of Inequality
The primary symbols used in inequalities are: the 'less than' symbol (<), the 'greater than' symbol (>), the 'less than or equal to' symbol (≤), and the 'greater than or equal to' symbol (≥). Each symbol defines a specific, non-equal relationship between the numbers or expressions it separates.
Section 3: A Practical Example
Consider the statement 'x > 7'. This inequality means that the variable 'x' can represent any number that is strictly greater than 7. For instance, 8, 9.5, and 150 are all valid solutions for x, but 7 and 6 are not. This contrasts with the equation x = 7, where x can only be 7.
Section 4: Importance and Applications
Inequalities are crucial in both pure mathematics and real-world applications for representing ranges, constraints, and conditions. They are used in optimization problems (e.g., finding the maximum profit), setting limits (e.g., a budget must be less than or equal to a certain amount), and defining the domains of functions in calculus.