# can anyone tell me what this mathematical symbol is?

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I can't even figure out how to "draw it" on here: it is two vertical lines, a number and then two more vertical lines - like an absolute except with an extra line on each side. Found this in our PSAT practice book. We've completed Algebra 1 and Geometry, both w/ Jacobs. Did we miss this somewhere?

Thanks

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It is the norm or length often used with a vector. What is the problem that was given using the symbol?

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The first:

For any value of x, ||x|| = 2/3x(squared)

the second:

What is the value of ||6(squared)||

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The first:

For any value of x, ||x|| = 2/3x(squared)

the second:

What is the value of ||6(squared)||

I've always used it for magnitude of a vector... but it sounds like what they mean is if ||x|| were to mean 2/3x^2 (or whatever), then how do you interpret ||whatever we want to put in here||.

Kind of like a different way to indicate a function...

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I've always used it for magnitude of a vector... but it sounds like what they mean is if ||x|| were to mean 2/3x^2 (or whatever), then how do you interpret ||whatever we want to put in here||.

Kind of like a different way to indicate a function...

Agreeing that they are defining a function using this symbol. Be careful--the function applies to this problem and the author could define the symbol as a different function in another problem. So forget my earlier comment on the symbol as a norm of a vector since the problem you gave has nothing to do with vectors.

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