How do you simplify something raised to the 1/2 power?

Answer 1

What you write is really general. For example you can not simplify this 2^{1/2} but you can simplify this 4^{1/2}=2. Similarly, you can not simplify this y(y^{1/2}) but you can simplify this (y^{2})^{1/2)=|y|.