MHB Show Interval On Number Line....1

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The discussion focuses on representing the interval |x| < 2 on a number line, leading to the solution -2 < x < 2. Participants confirm the correct notation with open parentheses indicating the boundaries. WolframAlpha is suggested as a useful tool for checking answers, but one user emphasizes the need for explanations rather than just solutions. The importance of clearly stating the need for understanding in posts is highlighted, as it helps others provide more relevant assistance. Overall, the conversation underscores the balance between using computational tools and seeking deeper comprehension in precalculus.
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Show interval on number line.

|x| < 2

Solution:

-2 < x < 2

<-----(---------)------>

Left side parentheses = -2

Right side parentheses = 2

Correct?
 
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Yes.

Have you heard of WolframAlpha? It's can be a very useful learning tool, especially for checking your answers.

Check this link and take note of the number line down the bottom. Open circles are equivalent to open brackets "(,)" closed circles, "[,]".

Wolfram|Alpha: Computational Knowledge Engine
 
I know about WolframAlpha but I am not looking just for the answer. I need an explanation as I travel through my precalculus textbook.
 
RTCNTC said:
I know about WolframAlpha but I am not looking just for the answer. I need an explanation as I travel through my precalculus textbook.

Then you need to make that clear in your post! In your OP you are asking if your working is correct, WolframAlpha can do the checking for you (for simple problems anyway). If you don't understand something, make it clear.
 

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