Function involving a negative square root HELP?

AI Thread Summary
The discussion centers on the function f(x) = √x / (x(x-1)) with x = -2, highlighting the impossibility of taking the square root of a negative number without involving complex numbers. The correct approach leads to a complex result of 1.41i / 6. There is confusion regarding whether a real number could be a valid answer, with one participant acknowledging the error in questioning this. The conversation emphasizes the need to recognize when complex numbers are necessary in mathematical functions. Ultimately, the conclusion reinforces that the function's output for negative inputs must be complex.
yobrojas
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As you can't take the square root of a negative number without introducing complex numbers, which would be the correct answer to this function:

Equation:

x = -2

f(x) = √x / (x(x-1))


Answer a) 1.41i / 6

or

Answer b) 0
 
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Since you start by saying "you can't take the square root of a negative number without introducing complex numbers", why would you even ask whether a real number is the answer?
 
Sorry about that, just realize what I said...Apologies!
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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