Solving second-degree inequalities, therefore, requires a good understanding of quadratic equations and inequalities. To solve such problems, we need to follow certain steps. The first step is to rearrange the inequality equation to place all the terms on one side of the inequality sign and simplify it as much as possible. For example, consider this inequality: 3x² – 11x + 10 > 0. We can begin by rearranging this inequality to look like: 3x² – 11x + 10 – 0 > 0.
The next step is to factor the quadratic equation and find its zeros. It is essential to find the values of x that make the inequality equation satisfy the inequality, i.e., the zeros of the quadratic equation. For example, using the quadratic formula, the zeros of the equation 3x² – 11x + 10 = 0 are 1.67 and 0.67. Thus, the critical points of this inequality are x=1.67 and x=0.67.
The next step is to sketch the graph of the quadratic equation with the critical points marked on it. This will help to locate the regions where the quadratic function is greater than zero or less than zero. If the inequality is greater than zero, the solution will be those values of x that are either less than the smaller zero or greater than the larger zero. Conversely, if the inequality is less than zero, the solution will be those values of x that are between the smaller zero and the larger zero.
For example, in our previous inequality 3x² – 11x + 10 > 0, the critical points were x=1.67 and x=0.67, and the quadratic function is greater than zero in the regions outside these points. Therefore, the solution to this inequality is x < 0.67 or x > 1.67.
It is also essential to remember that the inequality sign can also be less than or equal to (≤) or greater than or equal to (≥). When dealing with these equalities, the boundary points must be included in the solution. If the solution of a second-degree inequality is x=2 or x= 5, for example, we need to include the values of x between these two points, as well as the points themselves. Hence, the solution to the inequality x² – 7x + 10 ≥ 0 will be x ≤ 2 or x ≥ 5.
In conclusion, second-degree inequalities are vital in solving quadratic problems that require finding the regions where the quadratic function is greater or lesser than zero. Although the process of solving second-degree inequalities may seem challenging, following the steps mentioned above can help simplify this process. Once the critical points are located, and the graph of the quadratic equation is sketched, it becomes simpler to identify the solution. It is important to remember that the inequality sign can also be less than or equal to (≤) or greater than or equal to (≥), and the boundary points must be included in the solution.