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Example Questions
Example Question #22 : Algebra
Solve the quadratic inequality.
We begin by solving the equation for its zeros. This is done by changing the sign into an sign.
Since we know the zeros of the equation, we can then check the areas around the zeros since we naturally have split up the real line into three sections :
First we check
Therefore, the first interval can be included in our answer. Additionally, we know that satisfies the equation, therefore we can say with certainty that the interval is part of the answer.
Next we check something in the second interval. Let , then
Therefore the second interval cannot be included in the answer.
Lastly, we check the third interval. Let , then
Which does satisfy the original equation. Therefore the third interval can also be included in the answer. Since we know that satisfies the equation as well, we can include it in the interval as such:
Therefore,
Example Question #2 : Inequalities
Solve:
Method 1:
1) Multiply-out the left side then rewrite the inequality as an equation:
2) Now rewrite as a quadratic equation and solve the equation:
3) Next set up intervals using the solutions and test the original inequality to see where it holds true by using values for on each interval.
4) The interval between and holds true for the original inequality.
5) Solution:
Method 2:
Using a graphing calculator, find the graph. The function is below the x-axis (less than ) for the x-values . Using interval notation for , .
Method 3:
For the inequality , the variable expression in terms of is less than , and an inequality has a range of values that the solution is composed of. This means that each of the solution values for are strictly between the two solutions of . 'Between' is for a 'less than' case, 'Outside of' is for a 'greater than' case.
Example Question #1 : Solve And Graph Linear Inequalities
Solve and graph:
1) Write as two simple inequalities:
2) Solve the inequalities:
3) Write the final solution as a single compound inequality:
For interval notation:
4) Now graph:
Example Question #1 : Linear Inequalities
Solve for
In order to solve this equation, we must first isolate the absolute value. In this case, we do it by dividing both sides by which leaves us with:
When we work with absolute value equations, we're actually solving two equations. So, our next step is to set up these two equations:
and
In both cases we solve for by adding to both sides, leaving us with
and
This can be rewritten as
Example Question #2 : Linear Inequalities
Solve for
When we work with absolute value equations, we're actually solving two equations:
and
Adding to both sides leaves us with:
and
Dividing by in order to solve for allows us to reach our solution:
and
Which can be rewritten as:
Example Question #3 : Linear Inequalities
Solve for
In order to solve for we must first isolate the absolute value. In this case, we do it by dividing both sides by 2:
As with every absolute value problem, we set up our two equations:
and
We isolate by adding to both sides:
and
Finally, we divide by :
and
Example Question #4 : Linear Inequalities
Solve for .
Our first step in solving this equation is to isolate the absolute value. We do this by dividing both sides by
.
We then set up our two equations:
and .
Subtracting 4 from both sides leaves us with
and .
Lastly, we multiply both sides by 2, leaving us with :
and .
Which can be rewritten as:
Example Question #31 : Inequalities And Linear Programming
Solve for
We first need to isolate the absolute value, which we can do in two steps:
1. Add 2 to both sides:
2. Divide both sides by 4:
Our next step is to set up our two equations:
and
We can now solve the equations for by subtracting both sides by 8:
and
and then dividing them by 5:
and
Which can be rewritten as:
Example Question #1 : Solve Absolute Value Inequalities
Solve the following absolute value inequality:
First we need to get the expression with the absolute value sign by itself on one side of the inequality. We can do this by subtracting seven from both sides.
Next we need to set up two inequalities since the absolute value sign will make both a negative value and a positive value positive.
From here, subtract thirteen from both sides and then divide everything by four.
Example Question #8 : Linear Inequalities
Solve the following absolute value inequality:
First we need to get the expression with the absolute value sign by itself on one side of the inequality. We can do this by dividing both sides by three.
We now have two equations:
and
So, our solution is
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