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April 30th, 2017, 07:07 PM   #1
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Question is it possible for a function to have a positive or negative root?

sorry im not really good at math please don't judge me

for example f(x)=(cuberoot)x+8 is it still a function if for some instance it was f(x) = positive or negative cuberoot of x + 8.

Well i have not seen any example with that positive or negative cube root or square root so maybe the answer is no but why?

I wondered be when i was studying function inverses is was possible for a function to have inverse relations say for example
s=-16(t-2)^2

when you get its inverse it will be an inverse relation
t=2 (positive or negative squareroot of 68-s/4)

here positive and negative square roots where applied ....and i want to know why? what was the basis of doing that?

I hope you get my point im very confused right now ....
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April 30th, 2017, 07:32 PM   #2
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The is only one (real) cube root of a real number.

For example, $\sqrt[3]{8} = 2$ and that's the only (real) answer. $\sqrt[3]{8} \ne -2$ because $(-2)^3 = -8$, not $+8$.

With square roots, if there can be two real numbers that satisfy the equation.
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