Principal Root

[RalphB]

Hi! What is the principal root of -√100?
Is it 10 or -10?
Please give a reason or justification for your answer.
Thank You!

 

[topsquark]

See here.

Now, your given problem is a lot simpler than this. Clearly $$\sqrt{100} = 10$$ is the principle root. So $$-\sqrt{100} = -10$$.

-Dan

 

[Dr.Peterson]

Hi! What is the principal root of -√100?
Is it 10 or -10?
Please give a reason or justification for your answer.
Thank You!

I'm not sure what the question means. [MATH]-\sqrt{100}[/MATH] is not itself a root; it is the negative of a root. The term "principal root" applies to a root.

And even then, we don't say "What is the principal root of [MATH]\sqrt{100}[/MATH]?"; the symbol "√" means "the principal square root of", so you are asking, "What is the principal root of the principal square root of 100?"

Is it your intention to ask for the principal square root of -10? Or is this just a silly trick question?