Is the Solution to the Absolute Value Inequality x^2<4 then |x|<=2 Correct?

In summary, the conversation is discussing the statement "If x^2 < 4 then |x| <= 2" and whether it is true or false. The speaker believes it should be false based on their solution, but the text states it is true. There is confusion about whether this is a mistake or if it is logically true. The expert summarizer suggests that it is likely a typo, but also explains how it can be logically true.
  • #1
OceanSpring
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Question:
True or False If x^2<4 then |x|<=2

My solution:
I get -2<x<2 when I solve the problem so it should be false. Yet the text says its true? Is this a mistake? If |x| is equal to 2 then it should be a closed interval, not an open interval which seems to be correct to me.
 
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  • #2
OceanSpring said:
Question:
True or False If x^2<4 then |x|<=2

My solution:
I get -2<x<2 when I solve the problem so it should be false. Yet the text says its true? Is this a mistake? If |x| is equal to 2 then it should be a closed interval, not an open interval which seems to be correct to me.
x2 < 4 is equivalent to -2 < x < 2 or |x| < 2. What the text has appears to be a typo.
 
  • #3
OceanSpring said:
Question:
True or False If x^2<4 then |x|<=2

My solution:
I get -2<x<2 when I solve the problem so it should be false. Yet the text says its true? Is this a mistake? If |x| is equal to 2 then it should be a closed interval, not an open interval which seems to be correct to me.

It's probably a typo, although logically it is true:

If ##x^2 < 4## then ##|x| < 2## hence ##|x| \le 2##

If it were false, then there would be ##x## with ##|x| > 2## yet ##x^2 < 4##
 
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Related to Is the Solution to the Absolute Value Inequality x^2<4 then |x|<=2 Correct?

What is Absolute Value Inequality?

Absolute value inequality is a mathematical concept that compares the distance of a number from zero on a number line. It is represented by the symbol "|x|".

How do you solve Absolute Value Inequalities?

To solve absolute value inequalities, first isolate the absolute value term on one side of the inequality. Then, solve the inequality as two separate equations, one with a positive value and one with a negative value. The resulting solutions will form the solution set for the absolute value inequality.

What is the difference between Absolute Value Inequalities and Absolute Value Equations?

The main difference between absolute value inequalities and absolute value equations is that inequalities have more than one possible solution, while equations have only one solution. Inequalities are represented with the symbols "<" or ">" while equations are represented with an equal sign.

When do you use Absolute Value Inequalities in real life?

Absolute value inequalities are used in real life to represent situations where there are multiple possible solutions. For example, they can be used in finance to compare the profits of two different investments or in physics to calculate the range of possible values for a measurement.

Why is it important to understand Absolute Value Inequalities?

Understanding absolute value inequalities is important because they are used in many areas of mathematics, science, and everyday life. They allow us to compare and analyze data, make informed decisions, and solve complex problems. They also serve as a foundation for more advanced mathematical concepts.

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