Problem with notation for square roots

Harry_the_cat

Elite Member
Joined
Mar 16, 2016
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Are these two expressions the same? That is, can the square root symbol always be interpreted as raising to an exponent of \(\displaystyle \frac{1}{2}\).

1. \(\displaystyle \sqrt{(-1)^2}\)

2. \(\displaystyle ((-1)^2)^{\frac{1}{2}}\)

It would appear to me that

\(\displaystyle \sqrt{(-1)^2}=\sqrt{1}=1\)

whereas

\(\displaystyle ((-1)^2)^{\frac{1}{2}}= (-1)^{(2*\frac{1}{2})}=(-1)^1=-1\).

What's going on here? The two different notations imply a different order of operation, so they are not the same. Thoughts?
 

u will find some relevance
 
Thanks for the link, but they are not really addressing the notation issue of sqrt symbol vs raising to power of 1/2. And I'm not concerned with complex numbers.
 
Thanks for the link, but they are not really addressing the notation issue of sqrt symbol vs raising to power of 1/2. And I'm not concerned with complex numbers.
see the '27' eg there and post no 31 and please come to conversation I am still waiting
 
I still didn't understand of your explanation of taking the square root by just cancellation of squares part .
Please come to Conversation.
 
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