Calculating Real Values of Expressions

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A real value of an expression refers to a numerical output that can be calculated based on the expression's variables. To find the least possible real value of an expression, one effective method is to take the derivative, set it to zero, and analyze critical points. In the discussed expression, simplification reveals that certain terms cancel, making it easier to determine the minimum value. The minimum occurs at n=3/2, yielding a value of -9/4. Understanding these concepts is essential for accurately calculating real values in mathematical expressions.
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i'm not sure whether this is the right place to post this but i need to know what a real value of an expression is. also can anyone tell how i could find the least possible real value of an expression.
 
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omega360 said:
also can anyone tell how i could find the least possible real value of an expression.

Without context, how could we know how to answer this?

My best guess would be "take the derivative, set it equal to zero, and check each occurrence". There are less advanced answers (for those who don't know calculus yet) and more advanced answers (Richardson's theorem says if the expression is sufficiently (not very!) complicated, it's undecidable in general).
 
could you tell me how to find the least possible real value of this expression:(where n is a real number)
(n squared) minus (3n) plus [the square root of (n – 3)] minus [the square root of (n – 3)]
 
n^2 - 3n + \sqrt{n-3} - \sqrt{n-3}is what you wrote, and the last two terms cancel so it probably wasn't what you wanted.
 
Well, that would make it easy to find the minimum...
 
Agreed. Just to make sure we're on the same page, the answer would be

n=3/2, val=-9/4

True story?
 
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